Sample records for acetic acid acetic

AceticAcid commonly associated with vinegar; it is the most commercially important organic acid and is used to manufacture a wide range of chemical products, such as plastics and insecticides. Aceticacid is produced naturally by Aceto bacteria but, except for making vinegar, is usually made through synthetic processes. Ethanoic acid is used as herbicide, as a micro-biocide, as a fungicide and for pH adjustment.

Corn starch was pre-treated with aceticacid and then acetylated by acetic anhydride under microwave irradiation. The effects of molar ratios of these two reagents on the acetylation of starch were investigated. Starch acetate with a high degree of substitution (DS, 2.93) was obtained at a molar ratio (aceticacid\\/acetic anhydride) of 1:1. However, the DS should tend to decrease

Bacterial biofilms are known to be extremely tolerant toward antibiotics and other antimicrobial agents. These biofilms cause the persistence of chronic infections. Since antibiotics rarely resolve these infections, the only effective treatment of chronic infections is surgical removal of the infected implant, tissue, or organ and thereby the biofilm. Aceticacid is known for its antimicrobial effect on bacteria in general, but has never been thoroughly tested for its efficacy against bacterial biofilms. In this article, we describe complete eradication of both Gram-positive and Gram-negative biofilms using aceticacid both as a liquid and as a dry salt. In addition, we present our clinical experience of aceticacid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of aceticacid against bacterial biofilms. PMID:26155378

. This presentation will investigate the use of acid detection strips (A-D strips) to study aceticacid off gassing occurring in custom-made, cloth covered book boxes constructed and used by conservators in research libraries....

Four thermotolerant aceticacid bacteria designated as CMU1, CMU2, CMU3 and CMU4 were isolated from six honey samples produced by three native bee species in northern Thailand, namely the dwarf honey bee (Apis florea), Asian honey bee (A. cerena) and giant honey bee (A. dorsata). All isolates were tested for their tolerance to aceticacid and ethanol at 30?C and

A low-cost experiment to carry out the second-order reversible reaction of aceticacid esterification with ethanol to produce ethyl acetate is presented to illustrate concepts of kinetics and reactor modeling. The reaction is performed in a batch reactor, and the aceticacid concentration is measured by acid-base titration versus time. The…

Original article Ethanol and acetic-acid tolerance in Indian geographical populations of Drosophila clines of ethanol toler- ance (1.5-4.2%) and acetic-acid tolerance (2.9-4.9%) were observed in adult individuals of 4 geographical populations of Drosophila immigrans. Thus, both ethanol and acetic

Aceticacid is a weak organic acid exerting a toxic effect to most microorganisms at concentrations as low as 0.5 wt%. This toxic effect results mostly from aceticacid dissociation inside microbial cells, causing a decrease of intracellular pH and metabolic disturbance by the anion, among other deleterious effects. These microbial inhibition mechanisms enable aceticacid to be used as a preservative, although its usefulness is limited by the emergence of highly tolerant spoilage strains. Several biotechnological processes are also inhibited by the accumulation of aceticacid in the growth medium including production of bioethanol from lignocellulosics, wine making, and microbe-based production of aceticacid itself. To design better preservation strategies based on aceticacid and to improve the robustness of industrial biotechnological processes limited by this acid's toxicity, it is essential to deepen the understanding of the underlying toxicity mechanisms. In this sense, adaptive responses that improve tolerance to aceticacid have been well studied in Escherichia coli and Saccharomyces cerevisiae. Strains highly tolerant to aceticacid, either isolated from natural environments or specifically engineered for this effect, represent a unique reservoir of information that could increase our understanding of aceticacid tolerance and contribute to the design of additional tolerance mechanisms. In this article, the mechanisms underlying the aceticacid tolerance exhibited by several bacterial strains are reviewed, with emphasis on the knowledge gathered in aceticacid bacteria and E. coli. A comparison of how these bacterial adaptive responses to aceticacid stress fit to those described in the yeast Saccharomyces cerevisiae is also performed. A systematic comparison of the similarities and dissimilarities of the ways by which different microbial systems surpass the deleterious effects of aceticacid toxicity has not been performed so far, although such exchange of knowledge can open the door to the design of novel approaches aiming the development of aceticacid-tolerant strains with increased industrial robustness in a synthetic biology perspective. PMID:26142387

Gas, phase and rain concentrations of HCOOH and CH 3COOH have been measured at various sites in the savannah climatic region, a cloud forest site and a coastal site in Venezuela. Gas phase and rain water were sampled using the aqueous scrubber technique and a wet only collector, respectively. Analyses were made by ion chromatography. The results indicate that formic and aceticacids are important components of the Venezuelan atmosphere. They are homogeneously distributed, suggesting a widespread source. Boundary layer concentrations during the dry season (HCOOH, 1.8 ppbv; CH 3COOH, 1.25 ppbv) are higher than in the wet season (HCOOH, 1.0 ppbv; CH 3COOH, 0.7 ppbv), mainly due to a longer lifetime of the acid during the dry season (˜6 days) compared with the wet season (˜2 days). The overall concentrations in rain are 7.0 and 4.0 ?M for formic and aceticacids, respectively. The estimated annual total depositions are: HCOOH, 17 mmol m -2 yr -1 and CH 3COOH,10 mmol m -2 yr -1; around half of the acids are removed by dry deposition. It is established that a larger source (˜1.8 times) of both acids is present during the wet season. We speculate that atmospheric oxidation of hydrocarbons should be the main source of HCOOH and CH 3COOH in the Venezuelan atmosphere; soil emissions could make a significant contribution during the dry season.

An amperometric method was developed by using a lead working electrode in acetonitrile organic solution for detecting aceticacid. The mechanisms of electrochemical reaction were corresponding to the reduction of acetic ions in acetonitrile organic solution. The steady state amperometric current resulted from the reduction of acetic ions to produce the aldehyde in a two-electron process. In the organic sensing

Purpose – The purpose of this paper is to consider the effect of aceticacid and acetate on the anodic and cathodic reactions of carbon steel present in CO2 corrosion. Design\\/methodology\\/approach – The corrosion behaviour of carbon steel (N80) in CO2-saturated 1% NaCl solution at 50°C and 0.1 MPa was investigated by using weight-loss tests, electrochemical methods (polarization curves and

Indole-3-aceticacid is oxidized to oxindole-3-aceticacid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-aceticacid to oxindole-3-aceticacid in higher plants.

Original article Ethanol and acetic-acid tolerances in Drosophila melanogaster: similar maternal) Summary - Ethanol and acetic-acid tolerances were studied in a cross between 2 geo- graphic races disappeared in the F2. Further investigations demonstrated that for ethanol tolerance, the large difference

Radiolabeled oxindole-3-aceticacid was metabolized by roots, shoots, and caryopses of dark grown Zea mays seedlings to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-aceticacid-7'-O-beta-D-glycopyranoside with the simpler name of 7-hydroxyoxindole-3-aceticacid-glucoside. This compound was also formed from labeled indole-3-aceticacid supplied to intact seedlings and root segments. The glucoside of 7-hydroxyoxindole-3-aceticacid was also isolated as an endogenous compound in the caryopses and shoots of 4-day-old seedlings. It accumulates to a level of 4.8 nanomoles per plant in the kernel, more than 10 times the amount of oxindole-3-aceticacid. In the shoot it is present at levels comparable to that of oxindole-3-aceticacid and indole-3-aceticacid (62 picomoles per shoot). We conclude that 7-hydroxyoxindole-3-aceticacid-glucoside is a natural metabolite of indole-3-aceticacid in Z. mays seedlings. From the data presented in this paper and in previous work, we propose the following route as the principal catabolic pathway for indole-3-aceticacid in Zea seedlings: Indole-3-aceticacid --> Oxindole-3-aceticacid --> 7-Hydroxyoxindole-3-aceticacid --> 7-Hydroxyoxindole-3-aceticacid-glucoside.

As more and more exoplanets are discovered and the habitability of such planets is considered, one can turn to searching for the origin of life on Earth in order to better understand what makes a habitable planet. Activated aceticacid, or methyl thioacetate, has been proposed to be central to the origin of life on Earth, and also as an important energy currency molecule in early cellular evolution. We have investigated the hydrolysis of methyl thioacetate under various conditions. Its uncatalyzed rate of hydrolysis is about three orders of magnitude faster (K = 0.00663 s^-1; 100°C, pH 7.5, concentration = 0.33mM) than published rates for its catalyzed production making it unlikely to accumulate under prebiotic conditions. However, we also observed that methyl thioacetate was protected from hydrolysis when inside its own hydrophobic droplets. We found that methyl thioacetate protection from hydrolysis was also possible in droplets of hexane and in the membranes of nonanoic acid micelles. Thus, the hydrophobic regions of prebiotic micelles and early cell membranes could have offered a refuge for this energetic molecule increasing its lifetime in close proximity to the reactions for which it would be needed. Methyl thioacetate could thus be important for the origin of life on Earth and perhaps for better understanding the potential habitability of other planets.

Oxindole-3-aceticacid is the principal catabolite of indole-3-aceticacid in Zea mays seedlings. In this paper measurements of the turnover of oxindole-3-aceticacid are presented and used to calculate the rate of indole-3-aceticacid oxidation. [3H]Oxindole-3-aceticacid was applied to the endosperm of Zea mays seedlings and allowed to equilibrate for 24 h before the start of the experiment. The subsequent decrease in its specific activity was used to calculate the turnover rate. The average half-life of oxindole-3-aceticacid in the shoots was found to be 30 h while that in the kernels had an average half-life of 35h. Using previously published values of the pool sizes of oxindole-3-aceticacid in shoots and kernels from seedlings of the same age and variety, and grown under the same conditions, the rate of indole-3-aceticacid oxidation was calculated to be 1.1 pmol plant-1 h-1 in the shoots and 7.1 pmol plant-1 h-1 in the kernels.

Fermentation of milk permeate to produce aceticacid under anaerobic thermophilic conditions (approximately 60 degrees C) was studied. Although none of the known thermophilic acetogenic bacteria can ferment lactose, it has been found that one strain can use galactose and two strains can use lactate. Moorella thermoautotrophica DSM 7417 and M. thermoacetica DSM 2955 were able to convert lactate to acetate at thermophilic temperatures with a yield of approximately 0.93 g g(-1). Among the strains screened for their abilities to produce acetate and lactate from lactose, Clostridium thermolacticum DSM 2910 was found precisely to produce large amounts of lactate and acetate. However, it also produced significant amounts of ethanol, CO2 and H2. The lactate yield was affected by cell growth. During the exponential phase, acetate, ethanol, CO2 and H2 were the main products of fermentation with an equimolar acetate/ethanol ratio, whereas during the stationary phase, only lactic acid was produced with a yield of 4 mol per mol lactose, thus reaching the maximal theoretical value. When this bacterium was co-cultured with M. thermoautotrophica, lactose was first converted mainly to lactic acid, then to aceticacid, with a zero residual lactic acid concentration and an overall yield of acetate around 80%. Under such conditions, only 13% of the fermented lactose was converted to ethanol by C. thermolacticum. PMID:10784299

...2011-07-01 2011-07-01 false Aceticacid; exemption from the requirement...From Tolerances § 180.1258 Aceticacid; exemption from the requirement...residues of the biochemical pesticide aceticacid when used as a...

...2010-07-01 2010-07-01 false Aceticacid; exemption from the requirement...From Tolerances § 180.1258 Aceticacid; exemption from the requirement...residues of the biochemical pesticide aceticacid when used as a...

Cervical Intraepithelial Neoplasia (CIN) exhibits certain morphologic features that can be identified during a visual inspection exam. Immature and dysphasic cervical squamous epithelium turns white after application of aceticacid during the exam. The whitening process occurs visually over several minutes and subjectively discriminates between dysphasic and normal tissue. Digital imaging technologies allow us to assist the physician analyzing the aceticacid induced lesions (acetowhite region) in a fully automatic way. This paper reports a study designed to measure multiple parameters of the acetowhitening process from two images captured with a digital colposcope. One image is captured before the aceticacid application, and the other is captured after the aceticacid application. The spatial change of the acetowhitening is extracted using color and texture information in the post aceticacid image; the temporal change is extracted from the intensity and color changes between the post aceticacid and pre aceticacid images with an automatic alignment. The imaging and data analysis system has been evaluated with a total of 99 human subjects and demonstrate its potential to screening underserved women where access to skilled colposcopists is limited.

Ice crystalline layers were prepared from a binary eutectic mixture of aceticacid and water using layer melt crystallization. The crystalline layers were obtained under the conditions of the cooling temperature at 269, 268, and 267 K, the feed compositions of 0.5, 1.0, and 5.0 wt% aceticacid, and the cooling rates of 0.1, 0.5, and 1.0 K\\/min. After crystallization, sweating operations were

Liquid-liquid equilibria for the ternary systems water + aceticacid + ethyl acetate and water + aceticacid + isophorone (3,5,5-trimethyl-2-cyclohexen-1-one) were measured over the temperature range (283 to 313) K. The results were used to estimate the interaction parameters between each of the three compounds of the systems studied for the NRTL and UNIQUAC models. The estimated interaction parameters were successfully used to predict the equilibrium compositions by the two models; experimental data were successfully reproduced. The UNIQUAC model was the most accurate in correlating the overall equilibrium composition of the studied systems. Also the NRTL model satisfactorily predicted the equilibrium composition. Isophorone experimentally resulted in a better extraction capacity for aceticacid and in a lower miscibility with water.

The degradation of crystalline Si photovoltaic modules during damp-heat test was studied using some test modules with and without polymer film insertion by observing electrical and electroluminescence properties and by chemical analyses. Aceticacid generated by the hydrolysis decomposition of ethylene vinyl acetate used as an encapsulant is the main origin of degradation. The change in electroluminescence images is explained on the basis of the corrosion of electrodes by aceticacid. On the other hand, little change was observed at the pn junction even after damp-heat test for a long time. Therefore, carrier generation occurs even after degradation; however, such generated carriers cannot be collected owing to corrosion of electrodes. The guiding principle that module structure and module materials without saving aceticacid into the modules was obtained.

Monomers of (tetrazol-5-yl)-aceticacid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol-1 energy range and should be appreciably populated at the sublimation temperature (˜330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol-1) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol-1). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm-1, where the first OH stretching overtone vibrations of 1ccc and 2pcc occur. The reverse transformations could be induced by irradiations at 7010 and 7030 cm-1, transforming 1cct and 2pct back to 1ccc and 2pcc, also selectively. Besides the NIR-induced transformations, the photogenerated 1cct and 2pct forms also decay in N2 matrices back to 1ccc and 2pcc spontaneously, with characteristic decay times of hours (1H) and tens of minutes (2H). The decay mechanism is rationalized in terms of the proton tunneling. In crystals, TAA exists exclusively as 1H-tautomer. By contrast, the tautomeric composition of the matrix-isolated monomers was found to consist of both 1H- and 2H-tautomers, in comparable amounts. A mechanistic discussion of the tautomerization process occurring during sublimation, accounting also for the observed minor decomposition of TAA leading to CO2 and 5-methyl-tetrazole, is proposed.

We have studied the structure and photodissociation of Mg{sup +}-aceticacid clusters. Ab initio calculations suggest four relatively strongly bound ground state isomers for the [MgC{sub 2}H{sub 4}O{sub 2}]{sup +} complex. These isomers include the cis and trans forms of the Mg{sup +}-aceticacid association complex with Mg{sup +} bonded to the carbonyl O atom of aceticacid, the Mg{sup +}-aceticacid association complex with Mg{sup +} bonded to the hydroxyl O atom of aceticacid, or to a Mg{sup +}-ethenediol association complex. Photodissociation through the Mg{sup +}-based 3p

Mung bean seed inoculated with Salmonella Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes (3 to 5 log CFU/g) was exposed to gaseous aceticacid in an aluminum fumigation chamber. Salmonella Typhimurium and E. coli O157:H7 were not detected by enrichment of seeds treated with 242 microl of aceticacid per liter of air for 12 h at 45 degrees C. L. monocytogenes was recovered by enrichment from two of 10 25-g seed samples treated in this manner. Fumigation with gaseous aceticacid was also lethal to indigenous bacteria and fungi on mung bean seed. The treatment did not significantly reduce seed germination rates, and no differences in surface microstructure were observed between treated and untreated seed viewed by scanning electron microscopy. PMID:10456753

7-Hydroxy-2-indolinone-3-aceticacid was identified as a catabolite of indole-3-aceticacid in germinating kernels of Zea mays and found to be present in amounts of ca 3.1 nmol/kernel. 7-Hydroxy-2-indolinone-3-aceticacid was shown to be a biosynthetic intermediate between 2-indolinone-3-aceticacid and 7-hydroxy-2-indolinone-3-aceticacid-7'-O-glucoside in both kernels and roots of Zea mays. Further metabolism of 7-hydroxy-2-[5-3H]-indolinone-3-aceticacid-7'-O-glucoside occurred to yield tritiated water plus, as yet, uncharacterized products.

A thermodynamic analysis of hydrogen generation by aceticacid steam reforming has been carried out with respect to applications in solid oxide fuel cells. The effect of operating parameters on equilibrium composition has been examined focusing especially on hydrogen and carbon monoxide production, which are the fuels in this type of fuel cell. The temperature, steam to aceticacid ratio, and to a lesser extent pressure affect significantly the equilibrium product distribution due to their influence on steam reforming, thermal decomposition and water-gas shift reaction. The study shows that steam reforming of aceticacid with a steam to aceticacid ratio of 2 to 1 is thermodynamically feasible with hydrogen, carbon monoxide and water as the main products at the equilibrium at temperatures higher than 700 °C, and achieving CO/CO2 ratios higher than 1. Thus, it can be concluded that within the operation temperature range of solid oxide fuel cells - between 700 °C and 1000 °C - the production of a gas rich in hydrogen and carbon monoxide is promoted.

A cellulose-derived fraction of biomass pyrolysis vapor was simulated by evaporating acetol and aceticacid (AA) from flasks on a hot plate. The liquid in the flasks was infused with heated nitrogen. The vapor/nitrogen stream was superheated in a tube oven and condensed by contact with a cloud of ...

Vinegars are the product of scalar fermentations carried out by several groups of microorganisms acting at different moments\\u000a in time. The initial phase is generally represented by an alcoholic fermentation commonly carried out by yeasts. Lactic acid\\u000a bacteria (LAB) can also play a role in releasing ethanol and aceticacid from heterofermentative lactic acid fermentations.\\u000a Depending on the nature of

Reassesses a common textbook misconception that "...phenols cannot be esterified directly." Results of experiments are discussed and data tables provided of an effective method for the direct preparation of phenyl acetate. (CS)

Dichloroacetic Acid (DCAA) and trichloroacetic acid (TCAA) comprise a major fraction of the reaction products formed when water containing a variety of precursor humic materials is chlorinated. Both DCAA and TCAA administered in the drinking water increased the incidence of hepat...

...CAS Reg. No. 64-19-7) is known as ethanoic acid. It occurs naturally in plant and animal tissues. It is produced by fermentation of carbohydrates or by organic synthesis. The principal synthetic methods currently employed are oxidation of...

...CAS Reg. No. 64-19-7) is known as ethanoic acid. It occurs naturally in plant and animal tissues. It is produced by fermentation of carbohydrates or by organic synthesis. The principal synthetic methods currently employed are oxidation of...

...CAS Reg. No. 64-19-7) is known as ethanoic acid. It occurs naturally in plant and animal tissues. It is produced by fermentation of carbohydrates or by organic synthesis. The principal synthetic methods currently employed are oxidation of...

Monsanto's highly successful synthesis of aceticacid from methanol and carbon monoxide illustrates use of new starting materials to replace pretroleum-derived ethylene. Outlines the fundamental aspects of the aceticacid process and suggests ways of extending the synthesis to higher carboxylic acids. (JN)

Transient reaction of adsorbed monolayers of aceticacid was used to characterize the photocatalytic properties of titanium silicalite zeolites (TS-1). The TS-1 zeolites having Si/Ti ratios of 5, 12.5, and 50 are effective catalysts at room temperature for both photocatalytic oxidation (PCO) and decomposition (PCD) of aceticacid. The rates of PCO are higher than the rates of PCD for each catalyst. Aceticacid oxidized photocatalytically in 0.2% O2 to form gas-phase CO2 and CH4 and adsorbed H2O on the TS-1 catalysts, whereas no CH4 formed on Degussa P25 TiO2. Isotope labeling showed that, on both TiO2 and TS-1 catalysts, the alpha-carbon formed CO2 whereas the beta-carbon formed CH4 and CO2. The rates of oxidation of the two carbons have different dependencies on UV intensity. The catalysts with higher Si/Ti ratios adsorbed significantly more aceticacid, and the PCO rates per gram of titanium are highest on the TS-1 catalyst with the lowest Ti content, apparently because a larger fraction of the Ti atoms are surface atoms on this catalyst. During PCD in an inert atmosphere, CO2, CH4, and C2H6 formed on TiO2 and on the catalyst with a Si/Ti ratio of 5, but C2H6 was not detected on the other catalysts. The CO2/CH4 selectivity during PCD increased with increasing Si/Ti ratio. The first step in PCO and PCD on TS-1 catalysts appears to be similar and involves formation of a CH3 radical. PMID:11347941

The exploitation of aceticacid bacteria (AAB) has a long history in fermentation processes and now represents an emerging\\u000a field in biotechnological applications, especially with regard to the biosynthesis of useful chemicals with a potentially\\u000a high economic value and, in food science, through the standardization of microbiological processes for the manufacture of\\u000a both vinegar and other fermented beverages.

The valorisation of very low concentration of aceticacid (6%, w\\/w) was investigated by reacting with n-butanol and 2-ethyl-1-hexanol taking advantage of the different solubilities of aceticacid and acetic ester in water. The esterification of very diluted solution of aceticacid with alcohol is a reversible reaction and the conversion is greatly restricted by equilibrium limitation. Therefore, the peculiarity

(Benzamidooxy)aceticacid (common name benzadox) which has herbicidal properties was evaluated as a potential inhibitor of photosynthesis in C4 plants. Among enzymes of the C4 pathway, it was a relatively strong inhibitor of alanine aminotransferase in in vitro experiments at concentrations of 5mM. In benzadox treated leaves of Panicum miliaceum, a NAD-malic enzyme type C4 species, there was strong inhibition of both alanine and aspartate aminotransferase and of photosynthetic O2 evolution within one hour. Consistent with the inhibition of these enzymes of the C4 cycle, the pool sizes of metabolites of the cycle was altered: the aspartate level was increased two fold, while the levels of other metabolites such as pyruvate, alanine, oxalacetate and malate were decreased. Kinetic studies with partially purified alanine aminotransferase showed that benzadox is a competitive inhibitor with respect to alanine and a noncompetitive inhibitor with respect to 2-oxoglutarate. Comparisons between the structures and inhibitory actions of benzadox and (aminooxy)aceticacid, the latter a potent inhibitor of alanine and aspartate aminotransferases, suggest that in vivo, benzadox may exert its effect through metabolism to (aminooxy)aceticacid. PMID:24458342

SUMMARY The determination of citric acid with pyridine and acetic anhydride has been in- vestigated at reaction temperatures from 17 to 60 ° C. The optimum proportions of pyridine, acetic anhydride, water, and aceticacid for maximum color intensity and stability are given for each temperature. The procedure has been modified to eliminate the violent nature of the reaction, even

Plasmids pGE1 (2.5 kb), pGE2 (7.2 kb), and pGE3 (5.5 kb) were isolated from Gluconacetobacter europaeus KGMA0119, and sequence analyses revealed they harbored 3, 8, and 4 genes, respectively. Plasmid copy numbers (PCNs) were determined by real-time quantitative PCR at different stages of bacterial growth. When KGMA0119 was cultured in medium containing 0.4% ethanol and 0.5% aceticacid, PCN of pGE1 increased from 7 copies/genome in the logarithmic phase to a maximum of 12 copies/genome at the beginning of the stationary phase, before decreasing to 4 copies/genome in the late stationary phase. PCNs for pGE2 and pGE3 were maintained at 1-3 copies/genome during all phases of growth. Under a higher concentration of ethanol (3.2%) the PCN for pGE1 was slightly lower in all the growth stages, and those of pGE2 and pGE3 were unchanged. In the presence of 1.0% aceticacid, PCNs were higher for pGE1 (10 copies/genome) and pGE3 (6 copies/genome) during the logarithmic phase. Numbers for pGE2 did not change, indicating that pGE1 and pGE3 increase their PCNs in response to aceticacid. Plasmids pBE2 and pBE3 were constructed by ligating linearized pGE2 and pGE3 into pBR322. Both plasmids were replicable in Escherichia coli, Acetobacter pasteurianus and G. europaeus, highlighting their suitability as vectors for aceticacid bacteria. PMID:25575969

This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

The reaction kinetics of the esterification of ethylene glycol with aceticacid in the presence of cation exchange resin has been studied and kinetic models based on empirical and Langmuir approach has been developed. The Langmuir based model involving eight kinetic parameters fits experimental data much better compared to empirical model involving four kinetic parameters. The effect of temperature and catalyst loading on the reaction system has been analyzed. Further, the activation energy and frequency factor of the rate constants for Langmuir based model has been estimated.

Besides ethanol, aceticacid is produced in naturally fermenting sweet resources and is a significant environmental stress for fruit-breeding Drosophila populations and species. Although not related to the presence of an active alcohol dehydrogenase, adult aceticacid tolerance was found to correlate with ethanol tolerance when sensitive (Afrotropical) and resistant (European) natural populations of Drosophila melanogaster were compared. The same correlation was found when comparing various Drosophila species. Tolerance to aceticacid also correlated with the tolerance to longer aliphatic acids of three, four, or five carbons but did not correlate with the tolerance to inorganic acids (i.e., hydrochloric and sulfuric acids). These observations suggest that aceticacid is detoxified by the conversion of acetate into acetyl-CoA, a metabolic step also involved in ethanol detoxification. Future investigations on the adaptation of Drosophila to fermenting resources should consider selective effects of both ethanol and aceticacid. PMID:8475110

Aceticacid bacteria (AAB) play an important role during cocoa fermentation, as their main product, acetate, is a major driver for the development of the desired cocoa flavors. Here, we investigated the specialized metabolism of these bacteria under cocoa pulp fermentation-simulating conditions. A carefully designed combination of parallel 13C isotope labeling experiments allowed the elucidation of intracellular fluxes in the complex environment of cocoa pulp, when lactate and ethanol were included as primary substrates among undefined ingredients. We demonstrate that AAB exhibit a functionally separated metabolism during coconsumption of two-carbon and three-carbon substrates. Acetate is almost exclusively derived from ethanol, while lactate serves for the formation of acetoin and biomass building blocks. Although this is suboptimal for cellular energetics, this allows maximized growth and conversion rates. The functional separation results from a lack of phosphoenolpyruvate carboxykinase and malic enzymes, typically present in bacteria to interconnect metabolism. In fact, gluconeogenesis is driven by pyruvate phosphate dikinase. Consequently, a balanced ratio of lactate and ethanol is important for the optimum performance of AAB. As lactate and ethanol are individually supplied by lactic acid bacteria and yeasts during the initial phase of cocoa fermentation, respectively, this underlines the importance of a well-balanced microbial consortium for a successful fermentation process. Indeed, AAB performed the best and produced the largest amounts of acetate in mixed culture experiments when lactic acid bacteria and yeasts were both present. PMID:24837393

Aceticacid bacteria (AAB) play an important role during cocoa fermentation, as their main product, acetate, is a major driver for the development of the desired cocoa flavors. Here, we investigated the specialized metabolism of these bacteria under cocoa pulp fermentation-simulating conditions. A carefully designed combination of parallel 13C isotope labeling experiments allowed the elucidation of intracellular fluxes in the complex environment of cocoa pulp, when lactate and ethanol were included as primary substrates among undefined ingredients. We demonstrate that AAB exhibit a functionally separated metabolism during coconsumption of two-carbon and three-carbon substrates. Acetate is almost exclusively derived from ethanol, while lactate serves for the formation of acetoin and biomass building blocks. Although this is suboptimal for cellular energetics, this allows maximized growth and conversion rates. The functional separation results from a lack of phosphoenolpyruvate carboxykinase and malic enzymes, typically present in bacteria to interconnect metabolism. In fact, gluconeogenesis is driven by pyruvate phosphate dikinase. Consequently, a balanced ratio of lactate and ethanol is important for the optimum performance of AAB. As lactate and ethanol are individually supplied by lactic acid bacteria and yeasts during the initial phase of cocoa fermentation, respectively, this underlines the importance of a well-balanced microbial consortium for a successful fermentation process. Indeed, AAB performed the best and produced the largest amounts of acetate in mixed culture experiments when lactic acid bacteria and yeasts were both present. PMID:24837393

Fluxes of formic (HCOOH) and acetic (CH3COOH) acids between soils and the atmosphere were measured in a scrub-grass savanna and a semideciduous forest of Venezuela. High emissions of both acids were observed from savanna soils during daytime, with a daily contribution to the atmospheric boundary layer of about 0.15 ppb HCOOH and 0.07 ppb CH3COOH. Soil watering, simulating rainfall, produces a significant increase in CH3COOH emissions. Forest soils consumed these acids, with deposition velocities of 0.21 and 0.16 cm s-1. Savanna soils appear to be a significant source of HCOOH and CH3COOH to the tropical savanna atmosphere.

Etiolated corn tissues oxidase indole-3-aceticacid (IAA) to oxindole-3-aceticacid (OxIAA). This oxidation results in loss of auxin activity and may plant a role in regulating IAA-stimulated growth. The enzyme has been partially purified and characterized and shown to require O{sub 2}, and a heat-stable lipid-soluble corn factor which can be replaced by linolenic or linoleic acids in the oxidation of IAA. Corn oil was tested as a cofactor in the IAA oxidation reaction. Corn oil stimulated enzyme activity by 30% while trilinolein was inactive. The capacity of green tissue to oxidize IAA was examined by incubating leaf sections from 2 week old light-grown corn seedlings with {sup 14}C-IAA. OxIAA and IAA were separated from other IAA metabolites on a 3 ml anion exchange column. Of the IAA taken up by the sections, 13% was oxidized to OxIAA. This is the first evidence that green tissue of corn may also regulate IAA levels by oxidizing IAA to OxIAA.

In the present paper, we reported a cataluminescence (CTL) sensor using nanoporous In2O3 as sensing material to determine trace aceticacid in air. The proposed sensor showed high sensitivity and selectivity to aceticacid at optimal temperature of 293degC. Quantitative analysis was performed at a wavelength of 440 nm. The linear range of CTL intensity versus concentration of aceticacid

The photolysis of S2O82- was studied for the removal of aceticacid in aqueous solution and compared with the H2O2\\/UV system. The SO4- radicals generated from the UV irradiation of S2O82- ions yield a greater mineralization of aceticacid than the OH radicals. Aceticacid is oxidized by SO4- radicals without significant formation of intermediate by-products. Increasing system pH results

The potential inhibitory effect of acetate on p-toluic acid methanogenic fermentation was studied during the continuous operation at 5.3 days hydraulic retention time of an upflow anaerobic sludge blanket reactor fed with a synthetic waste-water containing 3.67 mmp-toluic acid as sole carbon and energy source. In the absence of acetate, a chemical oxygen demand removal efficiency of 56.8% and an

Nitrogen is an essential plant nutrient, widely applied as N-fertilizer to improve yield of agriculturally important crops. An interesting alternative to avoid or reduce the use of N-fertilizers could be the exploitation of plant growth-promoting bacteria (PGPB), capable of enhancing growth and yield of many plant species, several of agronomic and ecological significance. PGPB belong to diverse genera, including Azospirillum, Azotobacter, Herbaspirillum, Bacillus, Burkholderia, Pseudomonas, Rhizobium, and Gluconacetobacter, among others. They are capable of promoting plant growth through different mechanisms including (in some cases), the biological nitrogen fixation (BNF), the enzymatic reduction of the atmospheric dinitrogen (N(2)) to ammonia, catalyzed by nitrogenase. Aerobic bacteria able to oxidize ethanol to aceticacid in neutral or acid media are candidates of belonging to the family Acetobacteraceae. At present, this family has been divided into ten genera: Acetobacter, Gluconacetobacter, Gluconobacter, Acidomonas, Asaia, Kozakia, Saccharibacter, Swaminathania, Neoasaia, and Granulibacter. Among them, only three genera include N(2)-fixing species: Gluconacetobacter, Swaminathania and Acetobacter. The first N(2)-fixing aceticacid bacterium (AAB) was described in Brazil. It was found inside tissues of the sugarcane plant, and first named as Acetobacter diazotrophicus, but then renamed as Gluconacetobacter diazotrophicus. Later, two new species within the genus Gluconacetobacter, associated to coffee plants, were described in Mexico: G. johannae and G. azotocaptans. A salt-tolerant bacterium named Swaminathania salitolerans was found associated to wild rice plants. Recently, N(2)-fixing Acetobacter peroxydans and Acetobacter nitrogenifigens, associated with rice plants and Kombucha tea, respectively, were described in India. In this paper, recent advances involving nitrogen-fixing AAB are presented. Their natural habitats, physiological and genetic aspects, as well as their association with different plants and contribution through BNF are described as an overview. PMID:18177965

Aceticacid inhibits the metabolic activities of Saccharomyces cerevisiae. Therefore, a better understanding of how S. cerevisiae cells acquire the tolerance to aceticacid is of importance to develop robust yeast strains to be used in industry. To do this, we examined the transcriptional changes that occur at 12 h post-exposure to aceticacid, revealing that 56 and 58 genes were upregulated and downregulated, respectively. Functional categorization of them revealed that 22 protein synthesis genes and 14 stress response genes constituted the largest portion of the upregulated and downregulated genes, respectively. To evaluate the association of the regulated genes with aceticacid tolerance, 3 upregulated genes (DBP2, ASC1, and GND1) were selected among 34 non-protein synthesis genes, and 54 viable mutants individually deleted for the downregulated genes were retrieved from the non-essential haploid deletion library. Strains overexpressing ASC1 and GND1 displayed enhanced tolerance to aceticacid, whereas a strain overexpressing DBP2 was sensitive. Fifty of 54 deletion mutants displayed enhanced aceticacid tolerance. Three chosen deletion mutants (hsps82?, ato2?, and ssa3?) were also tolerant to benzoic acid but not propionic and sorbic acids. Moreover, all those five (two overexpressing and three deleted) strains were more efficient in proton efflux and lower in membrane permeability and internal hydrogen peroxide content than controls. Individually or in combination, those physiological changes are likely to contribute at least in part to enhanced aceticacid tolerance. Overall, information of our transcriptional profile was very useful to identify molecular factors associated with aceticacid tolerance. PMID:26062532

It is imperative that aceticacid is removed from a waste stream in the UREX+process so that nitric acid can be recycled and possible interference with downstreatm steps can be avoidec. Aceticacid arises from acetohydrozamic acid (AHA), and is used to suppress plutonium in the first step of the UREX+process. Later, it is hydrolyzed into hydroxyl amine nitrate and aceticacid. Many common separation technologies were examined, and solvent extraction was determined to be the best choice under process conditions. Solvents already used in the UREX+ process were then tested to determine if they would be sufficient for the removal of aceticacid. The tributyl phosphage (TBP)-dodecane diluent, used in both UREX and NPEX, was determined to be a solvent system that gave sufficient distribution coefficients for aceticacid in addition to a high separation factor from nitric acid.

Background: Free radicals are the known mechanisms responsible for inducing colitis with two origins: Inflammatory cells and tissues. Only the inflammatory cells can be controlled by corticosteroids. Our aim was to assess the importance of neutrophils as one of the inflammatory cells in inducing colitis and to evaluate the efficacy of corticosteroids in the treatment of inflammatory bowel disease (IBD). Materials and Methods: Thirty-six mice were divided into six groups of six mice each. Colitis was induced in three groups by exposing them to aceticacid through enema (group 1), ex vivo (group 3), and enema after immune suppression (group 5). Each group had one control group that was exposed to water injection instead of aceticacid. Tissue samples were evaluated and compared based on macroscopic damages and biochemical and pathological results. Results: Considering neutrophilic infiltration, there were significant differences between groups 1, 3, 5, and the control of group 1. Groups 3, 5, and their controls, and group 1 and the control of group 3 had significant differences in terms of goblet depletion. Based on tissue originated H2O2, we found significant differences between group 1 and its control and group 3, and also between groups 5 and the control of group 3. All the three groups were significantly different from their controls based on Ferric Reducing Ability of Plasma (FRAP) and such differences were also seen between group 1 with two other groups. Conclusion: Neutrophils may not be the only cause of oxidation process in colitis, and also makes the effectiveness of corticosteroids in the treatment of this disease doubtful. PMID:25337523

The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications. PMID:25328203

Aceticacid acts as a contact herbicide, injuring and killing plants by first destroying the cell membranes, which causes the rapid desiccation of the plant tissues. Vinegars with aceticacid concentrations of 11% or greater can burn the skin and cause serious to severe eye injury, including blindn...

The carbon dioxide corrosion electrochemistry of mild steel has been studied in the presence of high CO2 partial pressures and aceticacid (HAc). Potentiodynamic sweeps, linear polarization resistance (LPR) and weight loss (WL) experiments have been conducted to investigate the effects of flow velocity, CO2 partial pressure, and aceticacid concentration on the corrosion rate of mild steel. Electrochemical impedance

We have characterized a new strain, Bifidobacterium animalis subsp. lactis CECT 7953, obtained by random UV mutagenesis, which produces less aceticacid than the wild type (CECT 7954) in three different experimental settings: De Man-Rogosa-Sharpe broth without sodium acetate, resting cells, and skim milk. Genome sequencing revealed a single Phe-Ser substitution in the acetate kinase gene product that seems to be responsible for the strain's reduced acid production. Accordingly, acetate kinase specific activity was lower in the low acetate producer. Strain CECT 7953 produced less acetate, less ethanol, and more yoghourt-related volatile compounds in skim milk than the wild type did. Thus, CECT 7953 shows promising potential for the development of dairy products fermented exclusively by a bifidobacterial strain. PMID:22389372

The present studies showed that about 80% of the indole-3-aceticacid extractable from Avena kernels by aqueous acetone was esterified to polymers precipitable by ammonium sulfate and ethanol or acetone. The polymers were positively charged, being adsorbed to cation exchange columns at a pH of 3, or below, and eluted at a pH greater than 4. The polymers were heterogeneous with respect to size, about 5,000 to 20,000 daltons, and charge, exhibiting apparent pKa values of 4.2 and 4.7. The polymer fractions contained esterified IAA, anthrone-reactive material that liberated glucose upon acid hydrolysis, phenolic compounds, and peptidic material with a high proportion of hydrophobic amino acids. Since the esterified IAA was unstable, establishing polymer purity was not possible, and the designation IAA-glucoprotein fraction was adopted. Dehusked Avena kernels contained 8 mg/kg total IAA of which 5.5% was free and 94.5% esterified. IAA bound through a peptidic linkage was present, but in only trace amounts. PMID:16659621

(both molar percent and concentrat1on); not in an increase in ruminal propionic acid. This study ind1cates that the addition of 1. 5, 2. 0 and 2. 5X aceticacid to reconstituted grain results in a rumi nal acetic:propi oni c acid ratio similar... in total volatile fatty acid production from reconstitution have been reported in vitro (12) and 1n vivo (12, 31, 34). A more narrow acetic:propionic acid ratio was reported by Helm (12) in vitro and in vi vo from reconstituted sorghum gra1n compared...

Herein, we report the influence of different combinations of initial concentration of aceticacid and ethanol on the removal\\u000a of aceticacid from acidic wines by two commercial Saccharomyces cerevisiae strains S26 and S29. Both strains reduced the volatile acidity of an acidic wine (1.0 g?l?1 aceticacid and 11% (v\\/v) ethanol) by 78% and 48%, respectively. Aceticacid removal by

Half of U.S. aceticacid production is used in manufacturing vinyl acetate monomer (VAM) and is economical only in very large production plants. Nearly 80% of the VAM is produced by methanol carbonylation, which requires high temperatures and exotic construction materials and is energy intensive. Fermentation-derived aceticacid production allows for small-scale production at low temperatures, significantly reducing the energy requirement of the process. The goal of the project is to develop a scaleable production and separation process for fermentation-derived aceticacid. Synthesis gas (syngas) will be fermented to aceticacid, and the fermentation broth will be continuously neutralized with ammonia. The aceticacid product will be recovered from the ammonium acid broth using vapor-based membrane separation technology. The process is summarized in Figure 1. The two technical challenges to success are selecting and developing (1) microbial strains that efficiently ferment syngas to aceticacid in high salt environments and (2) membranes that efficiently separate ammonia from the aceticacid/water mixture and are stable at high enough temperature to facilitate high thermal cracking of the ammonium acetate salt. Fermentation - Microbial strains were procured from a variety of public culture collections (Table 1). Strains were incubated and grown in the presence of the ammonium acetate product and the fastest growing cultures were selected and incubated at higher product concentrations. An example of the performance of a selected culture is shown in Figure 2. Separations - Several membranes were considered. Testing was performed on a new product line produced by Sulzer Chemtech (Germany). These are tubular ceramic membranes with weak acid functionality (see Figure 3). The following results were observed: (1) The membranes were relatively fragile in a laboratory setting; (2) Thermally stable {at} 130 C in hot organic acids; (3) Aceticacid rejection > 99%; and (4) Moderate ammonia flux. The advantages of producing aceticacid by fermentation include its appropriateness for small-scale production, lower cost feedstocks, low energy membrane-based purification, and lower temperature and pressure requirements. Potential energy savings of using fermentation are estimated to be approximately 14 trillion Btu by 2020 from a reduction in natural gas use. Decreased transportation needs with regional plants will eliminate approximately 200 million gallons of diesel consumption, for combined savings of 45 trillion Btu. If the fermentation process captures new aceticacid production, savings could include an additional 5 trillion Btu from production and 7 trillion Btu from transportation energy.

A modified water-immiscible solvent useful in the extraction of aceticacid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. Solvent mixtures formed of such a modified solvent with a desired co-solvent, preferably a low boiling hydrocarbon, are useful in the extraction of aceticacid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of aceticacid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of aceticacid recovery. Methods for the direct extraction of aceticacid and the extractive fermentation of aceticacid also employ the modified solvents and increase efficiency of aceticacid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of aceticacid in solvent.

A modified water-immiscible solvent useful in the extraction of aceticacid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. Solvent mixtures formed of such a modified solvent with a desired co-solvent, preferably a low boiling hydrocarbon, are useful in the extraction of aceticacid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of aceticacid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of aceticacid recovery. Methods for the direct extraction of aceticacid and the extractive fermentation of aceticacid also employ the modified solvents and increase efficiency of aceticacid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of aceticacid in solvent.

Weak organic acids are widely used as preservatives and disinfectants in the food industry. Despite their widespread use, the antimicrobial mode of action of organic acids is still not fully understood. This study investigated the effect of aceticacid on the cell membranes and cellular energy generation of four Salmonella strains. Using a nucleic acid/protein assay, it was established that aceticacid did not cause leakage of intracellular components from the strains. A scanning electron microscopy study further confirmed that membrane disruption was not the antimicrobial mode of action of aceticacid. Some elongated Salmonella cells observed in the micrographs indicated a possibility that aceticacid may inhibit DNA synthesis in the bacterial cells. Using an ATP assay, it was found that at a neutral pH, aceticacid caused cellular energy depletion with an ADP/ATP ratio in the range between 0.48 and 2.63 (p<0.05) that was apparent for the four Salmonella strains. We suggest that this effect was probably due solely to the action of undissociated acid molecules. The antimicrobial effect of aceticacid was better under acidic conditions (ADP/ATP ratio of 5.56 ± 1.27; p<0.05), where the role of both pH and undissociated acid molecules can act together. We concluded that the inhibitory effect of aceticacid is not solely attributable to acidic pH but also to undissociated acid molecules. This finding has implication for the use of aceticacid as an antimicrobial against Salmonella on food products, such as chicken meat, which can buffer its pH. PMID:25562466

Two-dimensional gel electrophoretic analysis of the membrane fraction of Acetobacter aceti revealed the presence of several proteins that were produced in response to aceticacid. A 60-kDa protein, named AatA, which was mostly induced by aceticacid, was prepared; aatA was cloned on the basis of its NH2-terminal amino acid sequence. AatA, consisting of 591 amino acids and containing ATP-binding

Detonation failure experiments and detonation velocity measurements were carried out with homogeneous liquid compositions of nitric acid, aceticacid and water contained in steel tubes with different diameters. The criterion for failure or propagation of detonation was based upon the type of damage exhibited by the tubes after the experiments. Mixtures with the same critical diameter were determined by varying

The affinity of indole-3-aceticacid (IAA), indole-3-propionic acid, indole-3-butyric acid and 24 of their amino acid conjugates to immobilized human serum albumin, as expressed by the retention factor k (determined by HPLC), was dependent on (1) lipophilicity, (2) chirality and (3) functional groups in the amino acid moiety; in some cases conformation plays an additional role. Two lipophilicity-related parameters afforded

The effect of aceticacid, a lignocellulose hydrolysis by-product, on lipid accumulation by activated sludge cultures grown on glucose was investigated. This was done to assess the possible application of lignocellulose as low-cost and renewable fermentation substrates for biofuel feedstock production. Results: Biomass yield was reduced by around 54% at a 2 g L -1 aceticacid dosage but was increased by around 18% at 10 g L -1 aceticacid dosage relative to the control run. The final gravimetric lipid contents at 2 and 10 g L -1 aceticacid levels were 12.5 Ã?Â?Ã?Â± 0.7% and 8.8 Ã?Â?Ã?Â± 3.2% w/w, respectively, which were lower than the control (17.8 Ã?Â?Ã?Â± 2.8% w/w). However, biodiesel yields from activated sludge grown with aceticacid (5.6 Ã?Â?Ã?Â± 0.6% w/w for 2 g L -1 aceticacid and 4.2 Ã?Â?Ã?Â± 3.0% w/w for 10 g L -1 aceticacid) were higher than in raw activated sludge (1-2% w/w). The fatty acid profiles of the accumulated lipids were similar with conventional plant oil biodiesel feedstocks. Conclusions: Aceticacid enhanced biomass production by activated sludge at high levels but reduced lipid production. Further studies are needed to enhance aceticacid utilization by activated sludge microorganisms for lipid biosynthesis.

Recent research in microbe-insect symbiosis has shown that aceticacid bacteria (AAB) establish symbiotic relationships with several insects of the orders Diptera, Hymenoptera, Hemiptera, and Homoptera, all relying on sugar-based diets, such as nectars, fruit sugars, or phloem sap. To date, the fruit flies Drosophila melanogaster and Bactrocera oleae, mosquitoes of the genera Anopheles and Aedes, the honey bee Apis mellifera, the leafhopper Scaphoideus titanus, and the mealybug Saccharicoccus sacchari have been found to be associated with the bacterial genera Acetobacter, Gluconacetobacter, Gluconobacter, Asaia, and Saccharibacter and the novel genus Commensalibacter. AAB establish symbiotic associations with the insect midgut, a niche characterized by the availability of diet-derived carbohydrates and oxygen and by an acidic pH, selective factors that support AAB growth. AAB have been shown to actively colonize different insect tissues and organs, such as the epithelia of male and female reproductive organs, the Malpighian tubules, and the salivary glands. This complex topology of the symbiosis indicates that AAB possess the keys for passing through body barriers, allowing them to migrate to different organs of the host. Recently, AAB involvement in the regulation of innate immune system homeostasis of Drosophila has been shown, indicating a functional role in host survival. All of these lines of evidence indicate that AAB can play different roles in insect biology, not being restricted to the feeding habit of the host. The close association of AAB and their insect hosts has been confirmed by the demonstration of multiple modes of transmission between individuals and to their progeny that include vertical and horizontal transmission routes, comprising a venereal one. Taken together, the data indicate that AAB represent novel secondary symbionts of insects. PMID:20851977

ABSTRACT Volatiles are small air-transmittable chemicals with diverse biological activities. In this study, we showed that volatiles produced by the bacterium Bacillus subtilis had a profound effect on biofilm formation of neighboring B. subtilis cells that grew in proximity but were physically separated. We further demonstrated that one such volatile, aceticacid, is particularly potent in stimulating biofilm formation. Multiple lines of genetic evidence based on B. subtilis mutants that are defective in either aceticacid production or transportation suggest that B. subtilis uses aceticacid as a metabolic signal to coordinate the timing of biofilm formation. Lastly, we investigated how B. subtilis cells sense and respond to aceticacid in regulating biofilm formation. We showed the possible involvement of three sets of genes (ywbHG, ysbAB, and yxaKC), all encoding putative holin-antiholin-like proteins, in cells responding to aceticacid and stimulating biofilm formation. All three sets of genes were induced by acetate. A mutant with a triple mutation of those genes showed a severe delay in biofilm formation, whereas a strain overexpressing ywbHG showed early and robust biofilm formation. Results of our studies suggest that B. subtilis and possibly other bacteria use aceticacid as a metabolic signal to regulate biofilm formation as well as a quorum-sensing-like airborne signal to coordinate the timing of biofilm formation by physically separated cells in the community. PMID:26060272

Screening a library of overexpressing mutant alleles of the TATA-binding gene SPT15 yielded two Saccharomyces cerevisiae strains (MRRC 3252 and 3253) with enhanced tolerance to aceticacid. They were also tolerant to propionic acid and hydrogen peroxide. Transcriptome profile analysis identified 58 upregulated genes and 106 downregulated genes in MRRC 3252. Stress- and protein synthesis-related transcription factors were predominantly enriched in the upregulated and downregulated genes respectively. Eight deletion mutants for some of the highly downregulated genes were aceticacid-tolerant. The level of intracellular reactive oxygen species was considerably lessened in MRRC 3252 and 3253 upon exposure to aceticacid. Metabolome profile analysis revealed that intracellular concentrations of 5 and 102 metabolites were increased and decreased, respectively, in MRRC 3252, featuring a large increase of urea and a significant decrease of amino acids. The dur1/2?mutant, in which the urea degradation gene DUR1/2 is deleted, displayed enhanced tolerance to aceticacid. Enhanced tolerance to aceticacid was also observed on the medium containing a low concentration of amino acids. Taken together, this study identified two SPT15 alleles, nine gene deletions and low concentration of amino acids in the medium that confer enhanced tolerance to aceticacid. PMID:24761971

We characterized the biosynthesis of indole-3-aceticacid by the mycoherbicide Colletotrichum gloeosporioides f. sp. aeschynomene. Auxin production was tryptophan dependent. Compounds from the indole-3-acetamide and indole-3-pyruvic acid pathways were detected in culture filtrates. Feeding experiments and in vitro assay confirmed the presence of both pathways. Indole-3-acetamide was the major pathway utilized by the fungus to produce indole-3-aceticacid in culture. PMID:9835603

Seeds of several agriculturally important legumes are rich sources of the only halogenated plant hormone, 4-chloroindole-3-aceticacid. However, the biosynthesis of this auxin is poorly understood. Here, we show that in pea (Pisum sativum) seeds, 4-chloroindole-3-aceticacid is synthesized via the novel intermediate 4-chloroindole-3-pyruvic acid, which is produced from 4-chlorotryptophan by two aminotransferases, TRYPTOPHAN AMINOTRANSFERASE RELATED1 and TRYPTOPHAN AMINOTRANSFERASE RELATED2. We characterize a tar2 mutant, obtained by Targeting Induced Local Lesions in Genomes, the seeds of which contain dramatically reduced 4-chloroindole-3-aceticacid levels as they mature. We also show that the widespread auxin, indole-3-aceticacid, is synthesized by a parallel pathway in pea. PMID:22573801

An efficient and expedient synthetic route to 2-acylindole-3-aceticacids is described. This work first demonstrates a one-pot room-temperature indole ring construction via the in situ generation of indoline intermediate.

A sustainable method, with minimal pollution and low energy cost in comparison with the conventional smelting methods, is proposed for treating components of spent lead-acid battery pastes in aqueous organic acid(s). In this study, PbO, PbO2, and PbSO4, the three major components in a spent lead paste, were individually reacted with a mixture of aqueous sodium citrate and aceticacid solution. Pure lead citrate precursor of Pb3(C6H5O7)2 · 3H2O is the only product crystallized in each leaching experiment. Conditions were optimized for individual lead compounds which were then used as the basis for leaching real industrial spent paste. In this work, efficient leaching process is achieved and raw material cost is reduced by using aqueous sodium citrate and aceticacid, instead of aqueous sodium citrate and citric acid as reported in a pioneering hydrometallurgical method earlier. Aceticacid is not only cheaper than citric acid but is also more effective in aiding dissolution of the lead compounds thus speeding up the leaching process in comparison with citric acid. Lead citrate is readily crystallized from the aqueous solution due to its low solubility and can be combusted to directly produce leady oxide as a precursor for making new battery pastes. PMID:23500418

The recovery of aceticacid from its dilute aqueous solutions is a major problem in both petrochemical and fine chemical industries. The conventional methods of recovery are azeotropic distillation, simple distillation and liquid–liquid extraction. Physical separations such as distillation and extraction suffer from several drawbacks. The esterification of an aqueous solution (30%) of aceticacid with n-butanol\\/iso-amyl alcohol is a

Aceticacid (AA)-catalyzed liquid hot water (LHW) pretreatments on raw corn stover (RCS) were carried out at 195 °C at 15 min\\u000a with the aceticacid concentrations between 0 and 400 g\\/kg RCS. After pretreatment, the liquor fractions and water-insoluble\\u000a solids (WIS) were collected separately and tested in terms of the recoveries of glucan and xylan from both the liquor fractions\\u000a and the

In the production of aceticacid from methanol and carbon monoxide with the use of iodine compounds as the catalyst,tantalu m, zirconium, Hastelloy type alloys, and molybdenumcontaining steels are used for the production of equipment. The production medium for the acid in the stage of synthesis and purification at I00-185~ contains up to 17% water, methyl acetate, methyl iodide, methanol,

The release of inhibitory concentrations of aceticacid from lignocellulosic raw materials during hydrolysis is one of the main concerns for 2nd generation ethanol production. The undissociated form of aceticacid can enter the cell by diffusion through the plasma membrane and trigger several toxic effects, such as uncoupling and lowered intracellular pH. The effect of aceticacid on the ethanol production was investigated in continuous cultivations by adding medium containing 2.5 to 20.0 g·L-1 aceticacid at pH 5.0, at a dilution rate of 0.5 h-1. The cultivations were performed at both high (~25 g·L-1) and very high (100-200 g·L-1) yeast concentration by retaining the yeast cells inside the reactor by a cross-flow membrane in a membrane bioreactor. The yeast was able to steadily produce ethanol from 25 g·L-1 sucrose, at volumetric rates of 5-6 g·L-1·h-1 at aceticacid concentrations up to 15.0 g·L-1. However, the yeast continued to produce ethanol also at a concentration of 20 g·L-1 aceticacid but at a declining rate. The study thereby demonstrates the great potential of the membrane bioreactor for improving the robustness of the ethanol production based on lignocellulosic raw materials. PMID:25028956

The release of inhibitory concentrations of aceticacid from lignocellulosic raw materials during hydrolysis is one of the main concerns for 2nd generation ethanol production. The undissociated form of aceticacid can enter the cell by diffusion through the plasma membrane and trigger several toxic effects, such as uncoupling and lowered intracellular pH. The effect of aceticacid on the ethanol production was investigated in continuous cultivations by adding medium containing 2.5 to 20.0 g·L?1 aceticacid at pH 5.0, at a dilution rate of 0.5 h?1. The cultivations were performed at both high (~25 g·L?1) and very high (100–200 g·L?1) yeast concentration by retaining the yeast cells inside the reactor by a cross-flow membrane in a membrane bioreactor. The yeast was able to steadily produce ethanol from 25 g·L?1 sucrose, at volumetric rates of 5–6 g·L?1·h?1 at aceticacid concentrations up to 15.0 g·L?1. However, the yeast continued to produce ethanol also at a concentration of 20 g·L?1 aceticacid but at a declining rate. The study thereby demonstrates the great potential of the membrane bioreactor for improving the robustness of the ethanol production based on lignocellulosic raw materials. PMID:25028956

High aceticacid tolerance of Saccharomyces cerevisiae is a relevant phenotype in industrial biotechnology when using lignocellulosic hydrolysates as feedstock. A screening of 38 S. cerevisiae strains for tolerance to aceticacid revealed considerable differences, particularly with regard to the duration of the latency phase. To understand how this phenotype is quantitatively manifested, four strains exhibiting significant differences were studied in more detail. Our data show that the duration of the latency phase is primarily determined by the fraction of cells within the population that resume growth. Only this fraction contributed to the exponential growth observed after the latency phase, while all other cells persisted in a viable but non-proliferating state. A remarkable variation in the size of the fraction was observed among the tested strains differing by several orders of magnitude. In fact, only 11 out of 10(7) cells of the industrial bioethanol production strain Ethanol Red resumed growth after exposure to 157 mM aceticacid at pH 4.5, while this fraction was 3.6 × 10(6) (out of 10(7) cells) in the highly aceticacid tolerant isolate ATCC 96581. These strain-specific differences are genetically determined and represent a valuable starting point to identify genetic targets for future strain improvement. PMID:24645649

The electrochemical oxidation of 3,4-dihydroxyphenylacetic acid (DOPAC) on a carbon fiber microelectrode (CF) and a glassy carbon macroelectrode (GC) in glacial aceticacid solutions was investigated using voltammetric techniques. Voltammograms recorded at these electrodes show well-defined single waves or peaks. The proposed mechanism of the anodic oxidation of DOPAC consists of two successive one-electron one-proton steps. The loss of the

The entire mol­ecule of pallidol hexa­acetate {systematic name: (±)-(4bR,5R,9bR,10R)-5,10-bis­[4-(acet­yloxy)phen­yl]-4b,5,9b,10-tetra­hydro­indeno­[2,1-a]indene-1,3,6,8-tetrayl tetra­acetate} is completed by the application of twofold rotational symmetry in the title ethyl acetate solvate, C40H34O12·C4H8O2. The ethyl acetate mol­ecule was highly disordered and was treated with the SQUEEZE routine [Spek (2009 ?). Acta Cryst. D65, 148–155]; the crystallographic data take into account the presence of the solvent. In pallidol hexa­acetate, the dihedral angle between the fused five-membered rings (r.m.s. deviation = 0.100?Å) is 54.73?(6)°, indicating a significant fold in the mol­ecule. Significant twists between residues are also evident as seen in the dihedral angle of 80.70?(5)° between the five-membered ring and the pendent benzene ring to which it is attached. Similarly, the acetate residues are twisted with respect to the benzene ring to which they are attached [C—O(carb­oxy)—C—C torsion angles = ?70.24?(14), ?114.43?(10) and ?72.54?(13)°]. In the crystal, a three-dimensional architecture is sustained by C—H?O inter­actions which encompass channels in which the disordered ethyl acetate mol­ecules reside. PMID:24046702

Adsorption and reaction of aceticacid on a CeO2(1 1 1) surface was studied by a combination of ultra-highvacuum based methods including temperature desorption spectroscopy (TPD), soft X-ray photoelectronspectroscopy (sXPS), near edge X-ray absorption spectroscopy (NEXAFS) and reflection absorption IRspectroscopy (RAIRS), together with density functional theory (DFT) calculations. TPD shows that thedesorption products are strongly dependent upon the initial oxidation state of the CeO2surface, includingselectivity between acetone and acetaldehyde products. The combination of sXPS and NEXAFS demon-strate that acetate forms upon adsorption at low temperature and is stable to above 500 K, above whichpoint ketene, acetone and aceticacid desorb. DFT and RAIRS show that below 500 K, bridge bondedacetate coexists with a moiety formed by adsorption of an acetate at an oxygen vacancy, formed bywater desorption.

The extraction of rare earths from nitrate medium using three organophosphorus acids, 2-ethylhexyl phosphonic acid mono-2-ethylhexyl\\u000a ester (HEHEHP), di-(2-ethylhexyl) phosphoric acid (D2EHPA), bis(2,4,4-trimethylpentyl) phosphinic acid (Cyanex272), and their\\u000a mixtures with sec-octylphenoxy aceticacid (CA12) has been studied in detail. The mixtures have different extraction effects on various rare\\u000a earths. Synergistic extraction effects are only found when light rare earths and

The affinity of indole-3-aceticacid (IAA), indole-3-propionic acid, indole-3-butyric acid and 24 of their amino acid conjugates to immobilized human serum albumin, as expressed by the retention factor k (determined by HPLC), was dependent on (1) lipophilicity, (2) chirality and (3) functional groups in the amino acid moiety; in some cases conformation plays an additional role. Two lipophilicity-related parameters afforded quantitative correlations with k: retention on a C18 reversed-phase column (experimental approach) and the distance between the hydrophilic and hydrophobic poles of the molecules (in silico approach). Most compounds examined are possible metabolic precursors of IAA, an experimental tumor therapeutic. PMID:17459401

Indole-3-aceticacid (IAA) and gibberellic acid (GA3) enhanced the formation of roots on the stem cuttings of Abelmoschus esculentus. The effect increased considerably when both IAA and GA3 were applied together.

Zygosaccharomyces bailii is one of the most widely represented spoilage yeast species, being able to metabolise aceticacid in the presence of glucose. To clarify whether simultaneous utilisation of the two substrates affects growth efficiency, we examined growth in single- and mixed-substrate cultures with glucose and aceticacid. Our findings indicate that the biomass yield in the first phase of growth is the result of the weighted sum of the respective biomass yields on single-substrate medium, supporting the conclusion that biomass yield on each substrate is not affected by the presence of the other at pH 3.0 and 5.0, at least for the substrate concentrations examined. In vivo(13)C-NMR spectroscopy studies showed that the gluconeogenic pathway is not operational and that [2-(13)C]acetate is metabolised via the Krebs cycle leading to the production of glutamate labelled on C(2), C(3) and C(4). The incorporation of [U-(14)C]acetate in the cellular constituents resulted mainly in the labelling of the protein and lipid pools 51.5% and 31.5%, respectively. Overall, our data establish that glucose is metabolised primarily through the glycolytic pathway, and aceticacid is used as an additional source of acetyl-CoA both for lipid synthesis and the Krebs cycle. This study provides useful clues for the design of new strategies aimed at overcoming yeast spoilage in acidic, sugar-containing food environments. Moreover, the elucidation of the molecular basis underlying the resistance phenotype of Z. bailii to aceticacid will have a potential impact on the improvement of the performance of S. cerevisiae industrial strains often exposed to aceticacid stress conditions, such as in wine and bioethanol production. PMID:23285028

Phenylmercuric acetate is white to white-yellow crystalline powder that is odorless. This phenyl mercury compound is used mainly as a fungicide, herbicide, slimicide and bacteriocide. Phenylmercuric acid serves as a preservative in canned paint, eye ointments and drops, injectable solutions, skin disinfectants and in cosmetics products such as hair shampoos, mouthwashes and toothpastes. It is also used in contraceptive gels and foams. Phenylmercuric acetate is prepared by interaction of benzene with mercuric acetate in glacial aceticacid. Phenylmercuric acetate's former production and use as a fungicide and as a mildew inhibitor in paints may have resulted in its direct release to the environment. This substance is very toxic to aquatic organisms and may be hazardous to the environment.

Wine quality is related to its intrinsic visual, taste, or aroma characteristics and is reflected in the price paid for that wine. One of the most important wine faults is the excessive concentration of aceticacid which can cause a wine to take on vinegar aromas and reduce its varietal character. Thereby it is very important for the wine industry to have methods, like electronic noses, for real-time monitoring the excessive concentration of aceticacid in wines. However, aroma characterization of alcoholic beverages with sensor array electronic noses is a difficult challenge due to the masking effect of ethanol. In this work, in order to detect the presence of aceticacid in synthetic wine samples (aqueous ethanol solution at 10% v/v) we use a detection unit which consists of a commercial electronic nose and a HSS32 auto sampler, in combination with a neural network classifier (MLP). To find the characteristic vector representative of the sample that we want to classify, first we select the sensors, and the section of the sensors response curves, where the probability of detecting the presence of aceticacid will be higher, and then we apply Principal Component Analysis (PCA) such that each sensor response curve is represented by the coefficients of its first principal components. Results show that the PEN3 electronic nose is able to detect and discriminate wine samples doped with aceticacid in concentrations equal or greater than 2 g/L. PMID:23262483

The use of rock salt for deicing roads has many negative effects on automobiles, highway systems, and the environment. Calcium magnesium acetate, hence-forth denoted CMA, has been identified as a more desirable, environmentally benign solid deicer for high-ways, airport runaways, and similar applications. CMA is also of interest as an additive for scavenging sulfur in combustion processes so as to reduce emissions of sulfur oxides and as a catalyst for coal gasification. Different extractants (trioctylphosphine oxide and secondary, tertiary, and quaternary amines) and solid sorbents (tertiary and quaternary amines) were investigated as agents for recovery of aceticacid as part of a process for production of CMA from fermentation aceticacid. The pH and temperature dependencies for uptake of aceticacid by these extractants and sorbents were measured, along with the degrees of regeneration by aqueous suspensions of slaked dolomitic lime. These results enable identification of agents having optimal basicity. Among the extractants, the secondary amine Amberlite LA-2 gave the best combined performance for extraction and regeneration. Among the sorbents, a tertiary amine, Amberlite IRA-35, gave the best performance. Trioctylphosphine oxide does not maintain capacity in the pH range (about 6) most attractive for aceticacid fermentation. Slurred crushed dolomite is not sufficiently basic to accomplish regeneration.

The effect of aceticacid vapour on soil-borne fungi and root rot disease of cucumber plants under greenhouse conditions was studied. Aceticacid vapour at four concentrations was tested against linear growth and spore germination of some soil-borne fungi, in vitro. The most sensitive fungus to aceticacid vapours was Rhizoctonia solani which inhibited at 4 µl l, while Fusarium solani,

The native auxin, indole-3-aceticacid (IAA), is a major regulator of plant growth and development. Its nonuniform distribution between cells and tissues underlies the spatiotemporal coordination of many developmental events and responses to environmental stimuli. The regulation of auxin gradients and the formation of auxin maxima/minima most likely involve the regulation of both metabolic and transport processes. In this article, we have demonstrated that 2-oxindole-3-aceticacid (oxIAA) is a major primary IAA catabolite formed in Arabidopsis thaliana root tissues. OxIAA had little biological activity and was formed rapidly and irreversibly in response to increases in auxin levels. We further showed that there is cell type-specific regulation of oxIAA levels in the Arabidopsis root apex. We propose that oxIAA is an important element in the regulation of output from auxin gradients and, therefore, in the regulation of auxin homeostasis and response mechanisms. PMID:24163311

Indigenous soil samples were tested for Phosphate solubilization. Efficient phosphate solubilizng bacteria were isolated. Effect of four different media on phosphate solubilization were determined. Auxin production by these bacteria were determined via bioassay and high performance liquid chromatography by the bacteria in liquid culture. Indole aceticacid and indole butyric acid were produced by these bacteria in varying concentration with

Poly(3-thiophene aceticacid)\\/Fe3O4 nanocomposite is synthesized by the precipitation of Fe3O4 in the presence of poly(3-thiophene aceticacid) (P3TAA). Structural, surface, morphological, thermal properties and conductivity characterization\\/evaluation of the nanocomposite were performed by XRD, FT-IR, TEM, TGA, and conductivity measurements, respectively. The capping of P3TAA around Fe3O4 nanoparticles was confirmed by FT-IR spectroscopy, the interaction being via bridging oxygens of

We have successfully synthesized zinc sulphide (ZnS) nanospheresdeposited on glass and silicon on insulator substrates as an aceticacid sensor. Results show that nanospheresdeposited on silicon on insulator substrate at lower ZnCl2 concentration show better response and good recovery. We found out that the sensitivity of the ZnSnanosphereswere dependent on the surface morphology and that the morphology is affected by the ZnCl2 concentrations and the substrates used. Our results show a promising potential of ZnSnanospheresas an inexpensive alternative sensing material to the existing aceticacid detectors.

...form. It is produced synthetically by the neutralization of aceticacid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food...

...form. It is produced synthetically by the neutralization of aceticacid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food...

...form. It is produced synthetically by the neutralization of aceticacid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food...

...form. It is produced synthetically by the neutralization of aceticacid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food...

...form. It is produced synthetically by the neutralization of aceticacid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food...

The effect of aceticacid and hydrochloric acid (HCl) deamidation pretreatment on the susceptibility of wheat gluten to enzymatic hydrolysis by Pancreatin and sensory characteristics of the resultant hydrolysates was investigated. At two degrees of deamidation (24% and 60%, with or without moisture-heating, respectively), wheat gluten pretreated by aceticacid deamidation was more susceptible to be hydrolyzed as evaluated by

Single crystal of aceticacid, monofluoroacetic acid, and glycolic acid have been irradiated at low temperature and investigated with ESR. The main purpose of the work was to obtain data for the structure and the reactions of the primary reduction products, i.e. the molecular anions. The anions of aceticacid and glycolic acid are stable at 77 K. The monofluoracetic acid anion could not be observed even at 3 K, but a decay product tentatively assigned to the F -… CH 2COOH adduct was detected. The glycolic acid anion decomposes by elimination of water to .CH 2COOH. The radical products .CFH 2 and .C(OH)H 2 were observed in monofluoracetic and glycolic acid, respectively. They are probably formed by decomposition of the molecular cations.

When using microorganisms as cell factories in the production of bio-based fuels or chemicals from lignocellulosic hydrolysate, inhibitory concentrations of aceticacid, released from the biomass, reduce the production rate. The undissociated form of aceticacid enters the cell by passive diffusion across the lipid bilayer, mediating toxic effects inside the cell. In order to elucidate a possible link between lipid composition and aceticacid stress, the present study presents detailed lipidomic profiling of the major lipid species found in the plasma membrane, including glycerophospholipids, sphingolipids and sterols, in Saccharomyces cerevisiae (CEN.PK 113_7D) and Zygosaccharomyces bailii (CBS7555) cultured with aceticacid. Detailed physiological characterization of the response of the two yeasts to aceticacid has also been performed in aerobic batch cultivations using bioreactors. Physiological characterization revealed, as expected, that Z. bailii is more tolerant to aceticacid than S. cerevisiae. Z. bailii grew at aceticacid concentrations above 24 g L?1, while limited growth of S. cerevisiae was observed after 11 h when cultured with only 12 g L?1 aceticacid. Detailed lipidomic profiling using electrospray ionization, multiple-reaction-monitoring mass spectrometry (ESI-MRM-MS) showed remarkable changes in the glycerophospholipid composition of Z. bailii, including an increase in saturated glycerophospholipids and considerable increases in complex sphingolipids in both S. cerevisiae (IPC 6.2×, MIPC 9.1×, M(IP)2C 2.2×) and Z. bailii (IPC 4.9×, MIPC 2.7×, M(IP)2C 2.7×), when cultured with aceticacid. In addition, the basal level of complex sphingolipids was significantly higher in Z. bailii than in S. cerevisiae, further emphasizing the proposed link between lipid saturation, high sphingolipid levels and aceticacid tolerance. The results also suggest that aceticacid tolerance is associated with the ability of a given strain to generate large rearrangements in its lipid profile. PMID:24023914

The addition of acetate ion to an O2-saturated mixed solution of acetonitrile and water containing oxalic acid as a reductant and 2-phenyl-4-(1-naphthyl)quinolinium ion (QuPh(+)-NA) as a photocatalyst dramatically enhanced the turnover number of hydrogen peroxide (H2O2) production. In this photocatalytic H2O2 production, a base is required to facilitate deprotonation of oxalic acid forming oxalate dianion, which acts as an actual electron donor, whereas a Brønsted acid is also necessary to protonate O2(•-) for production of H2O2 by disproportionation. The addition of acetate ion to a reaction solution facilitates both the deprotonation of oxalic acid and the protonation of O2(•-) owing to a pH buffer effect. The quantum yield of the photocatalytic H2O2 production under photoirradiation (? = 334 nm) of an O2-saturated acetonitrile-water mixed solution containing acetate ion, oxalic acid and QuPh(+)-NA was determined to be as high as 0.34, which is more than double the quantum yield obtained by using oxalate salt as an electron donor without acetate ion (0.14). In addition, the turnover number of QuPh(+)-NA reached more than 340. The reaction mechanism and the effect of solvent composition on the photocatalytic H2O2 production were scrutinized by using nanosecond laser flash photolysis. PMID:23631436

Microbes tailor macromolecules and metabolism to overcome specific environmental challenges. Aceticacid bacteria perform the aerobic oxidation of ethanol to aceticacid and are generally resistant to high levels of these two membrane-permeable poisons. The citric acid cycle (CAC) is linked to aceticacid resistance in Acetobacter aceti by several observations, among them the oxidation of acetate to CO2 by highly resistant aceticacid bacteria and the previously unexplained role of A. aceti citrate synthase (AarA) in aceticacid resistance at a low pH. Here we assign specific biochemical roles to the other components of the A. aceti strain 1023 aarABC region. AarC is succinyl-coenzyme A (CoA):acetate CoA-transferase, which replaces succinyl-CoA synthetase in a variant CAC. This new bypass appears to reduce metabolic demand for free CoA, reliance upon nucleotide pools, and the likely effect of variable cytoplasmic pH upon CAC flux. The putative aarB gene is reassigned to SixA, a known activator of CAC flux. Carbon overflow pathways are triggered in many bacteria during metabolic limitation, which typically leads to the production and diffusive loss of acetate. Since acetate overflow is not feasible for A. aceti, a CO2 loss strategy that allows aceticacid removal without substrate-level (de)phosphorylation may instead be employed. All three aar genes, therefore, support flux through a complete but unorthodox CAC that is needed to lower cytoplasmic acetate levels. PMID:18502856

Microbes tailor macromolecules and metabolism to overcome specific environmental challenges. Aceticacid bacteria perform the aerobic oxidation of ethanol to aceticacid and are generally resistant to high levels of these two membrane-permeable poisons. The citric acid cycle (CAC) is linked to aceticacid resistance in Acetobacter aceti by several observations, among them the oxidation of acetate to CO2 by highly resistant aceticacid bacteria and the previously unexplained role of A. aceti citrate synthase (AarA) in aceticacid resistance at a low pH. Here we assign specific biochemical roles to the other components of the A. aceti strain 1023 aarABC region. AarC is succinyl-coenzyme A (CoA):acetate CoA-transferase, which replaces succinyl-CoA synthetase in a variant CAC. This new bypass appears to reduce metabolic demand for free CoA, reliance upon nucleotide pools, and the likely effect of variable cytoplasmic pH upon CAC flux. The putative aarB gene is reassigned to SixA, a known activator of CAC flux. Carbon overflow pathways are triggered in many bacteria during metabolic limitation, which typically leads to the production and diffusive loss of acetate. Since acetate overflow is not feasible for A. aceti, a CO(2) loss strategy that allows aceticacid removal without substrate-level (de)phosphorylation may instead be employed. All three aar genes, therefore, support flux through a complete but unorthodox CAC that is needed to lower cytoplasmic acetate levels. PMID:18502856

A novel colorimetric luminescence sensor strip for the detection of indole-3-aceticacid (IAA) has been fabricated by using green emissive quantum dots of cadmium telluride (CdTe QDs) as a background layer and a red emissive europium chelate, [4?-(9-anthryl)-2,2?:6?,2?-terpyridine-6,6?-diyl]bis(methylenenitrilo) tetrakis(acetate)-Eu3+ (ATTA-Eu3+), as a specific sensing layer coated on the surface of glass slide, respectively. The luminescence response of the sensor strip

INDOLYL-3-ACETICacid (IAA) applied to intact plants may induce specific morphogenetic changes, by affecting the differentiation of certain organs in those parts of the plants to which it is transported. The causal relationship between endogenous and applied growth substances and the sex expression of cucumber plants was extensively studied in this laboratory1. The use of radioactive IAA makes possible an

The catalytic properties of anionic and cationic peanut peroxidases with regards to the oxidation of indole-3-aceticacid (IAA) by molecular oxygen at low pH have been studied. Transient kinetic studies demonstrate that only cationic peroxidases (peanut and horseradish) but not anionic peroxidases (such as anionic tobacco and anionic peanut peroxidases) form a stable compound III in the course of IAA

Feeding fermented liquid feed (FLF) to pigs has proven to benefit gastrointestinal health of the animals. However, growth performance data of piglets and growing pigs fed FLF are variable and often a lower feed intake compared to feeding non-FLF or dry feed has been observed. Accumulation of microbial metabolites, namely aceticacid, possibly in combination with low feed pH, has

This research addresses itself to the study of the mechanism of the aceticacid decarboxylation in Na-Montmorillonite exposed to ionizing radiation. The results obtained indicated that the decarboxylation reaction is enhanced several times by the irradiation. This behavior is probably due to an oxidation reaction at the edges of the clay. Also it is by energy transfer from the clay

The dividing wall column (DWC) has gained increasing application in a variety of chemical processes because of its potentiality in energy and capital cost savings in multicomponent separations. The main objective in this work is investigation of its use for removing the bottleneck phenomenon within the column when increasing the throughput of an existing distillation process, particularly, the aceticacid

The preferential pervaporation of aceticacid over water is achieved with silicalite filled polydimethylsiloxane (PDMS) membranes. The effect of silicalite addition is not positive at the feed temperature of 25°C, but improves with increasing feed temperature. At a feed temperature of 45°C, silicalite addition enhances not only the separation factor but also the permeation flux of the pervaporation. This improvement

Protein denaturation plays a crucial role in cellular processes. In this study, denaturation of HIV-1 Protease (PR) was investigated by all-atom MD simulations in explicit solvent. The PR dimer and monomer were simulated separately in 9 M aceticacid (9 M AcOH) solution and water to study the denaturation process of PR in aceticacid environment. Direct visualization of the denaturation dynamics that is readily available from such simulations has been presented. Our simulations in 9 M AcOH reveal that the PR denaturation begins by separation of dimer into intact monomers and it is only after this separation that the monomer units start denaturing. The denaturation of the monomers is flagged off by the loss of crucial interactions between the ?-helix at C-terminal and surrounding ?-strands. This causes the structure to transit from the equilibrium dynamics to random non-equilibrating dynamics. Residence time calculations indicate that denaturation occurs via direct interaction of the aceticacid molecules with certain regions of the protein in 9 M AcOH. All these observations have helped to decipher a picture of the early events in aceticacid denaturation of PR and have illustrated that the ?-helix and the ?-sheet at the C-terminus of a native and functional PR dimer should maintain both the stability and the function of the enzyme and thus present newer targets for blocking PR function. PMID:21738569

We present the first detailed comparative study of the adsorption and thermal processing of the three astrophysically important C2O2H4 isomers glycolaldehyde, methyl formate, and aceticacid adsorbed on a graphitic grain analogue at 20 K. The ability of the individual molecule to form intermolecular hydrogen bonds is extremely important, dictating the growth modes of the ice on the surface and the measured desorption energies. Methyl formate forms only weak intermolecular bonds and hence wets the graphite surface, forming monolayer, bilayer, and multilayer ices, with the multilayer having a desorption energy of 35 kJ mol(-1). In contrast, glycolaldehyde and aceticacid dewet the surface, forming clusters even at the very lowest coverages. The strength of the intermolecular hydrogen bonding for glycolaldehyde and aceticacid is reflected in their desorption energies (46.8 and 55 kJ mol(-1), respectively), which are comparable to those measured for other hydrogen-bonded species such as water. Infrared spectra show that all three isomers undergo structural changes as a result of thermal processing. In the case of aceticacid and glycolaldehyde, this can be assigned to the formation of well-ordered, crystalline, structures where the molecules form chains of hydrogen-bonded moieties. The data reported here are of relevance to astrochemical studies of hot cores and star-forming regions and can be used to model desorption from interstellar ices during the warm up phase with particular importance for complex organic molecules. PMID:26057183

Phenylacetaldehyde is a flower volatile and attractant for many nectar-seeking moths. Aceticacid is a microbial fermentation product that is present in insect sweet baits. It is weakly attractive to some moths and other insects, but can be additive or synergistic with other compounds to make more p...

Recently, we reported that a combination of indole-3-aceticacid (IAA) and horseradish peroxidase (HRP) induces apoptosis in G361 human melanoma cells. However, the apoptotic mechanism involved has been poorly studied. It is known that when IAA is oxidized by HRP, free radicals are produced, and since oxidative stress can induce apoptosis, we investigated whether reactive oxygen species (ROS) are involved

Nine Species of social wasps were captured in traps baited with aceticacid, isobutanol, heptyl butyrate and combinations of aceticacid and either isobutanol or heptyl butrate. Three yellowjacket species in the Vespula rufa species group were captured in traps (Vespula acadica (Sladen), Vespula co...

Separation of aceticacid\\/water mixtures by pervaporation was attempted over a range of compositions using polydimethylsiloxane (PDMS), aromatic polyamide (PA), and laminated polydimethylsiloxane-aromatic polyamide membranes. PDMS membranes are hydrophobic and aceticacid selective, whereas PA membranes are hydrophilic and water selective. When PDMS and PA membranes were laminated, with PDMS on the top side and in contact with the feed,

A modified water-immiscible solvent useful in the extraction of aceticacid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. This solvent is substantially devoid of mono-alkyl amines and alcohols. Solvent mixtures formed of such a modified solvent with a desired cosolvent, preferably a low boiling hydrocarbon which forms an azeotrope with water are useful in the extraction of aceticacid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of aceticacid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of aceticacid recovery. Methods for the direct extraction of aceticacid and the extractive fermentation of aceticacid also employ the modified solvents and increase efficiency of aceticacid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of aceticacid in solvent.

A modified water-immiscible solvent useful in the extraction of aceticacid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. This solvent is substantially devoid of mono-alkyl amines and alcohols. Solvent mixtures formed of such a modified solvent with a desired cosolvent, preferably a low boiling hydrocarbon which forms an azeotrope with water are useful in the extraction of aceticacid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of aceticacid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of aceticacid recovery. Methods for the direct extraction of aceticacid and the extractive fermentation of aceticacid also employ the modified solvents and increase efficiency of aceticacid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of aceticacid in solvent.

The degradation of lactic acid under anoxic conditions was studied in several strains of Lactobacillus buchneri and in close relatives such as Lactobacillus parabuchneri, Lactobacillus kefir, and Lactobacillus hilgardii. Of these lactobacilli, L. buchneri and L. parabuchneri were able to degrade lactic acid under anoxic conditions, without requiring an external electron acceptor. Each mole of lactic acid was converted into approximately 0.5 mol of aceticacid, 0.5 mol of 1,2-propanediol, and traces of ethanol. Based on stoichiometry studies and the high levels of NAD-linked 1,2-propanediol-dependent oxidoreductase (530 to 790 nmol min?1 mg of protein?1), a novel pathway for anaerobic lactic acid degradation is proposed. The anaerobic degradation of lactic acid by L. buchneri does not support cell growth and is pH dependent. Acidic conditions are needed to induce the lactic-acid-degrading capacity of the cells and to maintain the lactic-acid-degrading activity. At a pH above 5.8 hardly any lactic acid degradation was observed. The exact function of anaerobic lactic acid degradation by L. buchneri is not certain, but some results indicate that it plays a role in maintaining cell viability. PMID:11133436

A water based cerium oxide precursor solution using nitrilo-tri-acetic-acid (NTA) and aceticacid as complexing agents is described in detail. This precursor solution is used for the deposition of epitaxial CeO{sub 2} layers on Ni-5at%W substrates by dip-coating. The influence of the complexation behavior on the formation of transparent, homogeneous solutions and gels has been studied. It is found that ethylenediamine plays an important role in the gelification. The growth conditions for cerium oxide films were Ar-5% gas processing atmosphere, a solution concentration level of 0.25 M, a dwell time of 60 min at 900 {sup o}C and 5-30 min at 1050 {sup o}C. X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), pole figures and spectroscopic ellipsometry were used to characterize the CeO{sub 2} films with different thicknesses. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) was used to determine the carbon residue level in the surface of the cerium oxide film, which was found to be lower than 0.01%. Textured films with a thickness of 50 nm were obtained. - Graphical abstract: Study of the complexation and hydrolysis behavior of Ce{sup 4+} ions in the presence of nitrilo-tri-aceticacid and the subsequent development of an aqueous chemical solution deposition route suited for the processing of textured CeO{sub 2} buffer layers on Ni-W tapes.

Naphthenic acids are a complex mixture of organic components, some of which include saturated alkyl-substituted cycloaliphatic carboxylic acids and acyclic aliphatic acids. They are naturally found in hydrocarbon deposits like oil sand, petroleum, bitumen and crude oil. In this study, the oxidation of a relatively high molecular weight naphthenic acid (Dicyclohexyl aceticacid) was investigated using ozonation, ultrasonication and hydrogen peroxide alone and their combinations. Effects on oxidation of dicyclohexyl aceticacid (DAA) were measured for different concentrations of ozone ranging between 0.7 to 3.3 mg L(-1) and pH in the range 6 to 10. Ultrasonication and hydrogen peroxide alone were not effective to oxidize dicyclohexyl aceticacid, but combining ultrasonication with H2O2 had a significant effect on oxidation of dicyclohexyl aceticacid with maximum removal reaching to 84 ± 2.2% with 81 ± 2.1% reduction in chemical oxygen demand (COD). Synergistic effects were observed for combining ultrasonication with ozonation and resulted in 100% DAA removal with 98 ± 0.8% reduction in COD within 15 min at 3.3 mg L(-1) ozone concentration and 130 Watts ultrasonication power. The reaction conditions obtained for the maximum oxidation of DAA and COD removal were used for the degradation of naphthenic acids mixture extracted from oil sands process water (OSPW). The percentage oxidation of NAs mixture extracted from OSPW was 89.3 ± 1.1% in ozonation and combined ozonation and ultrasonication, but COD removal observed was 65 ± 1.2% and 78 ± 1.4% for ozonation and combined ozonation and ultrasonication treatments, respectively. PMID:25137539

The gamma-irradiation of 0.8 mol dm-3 aqueous, oxygen-free aceticacid solutions was investigated in the presence or absence of Na-montmorillonite. H2, CH4, CO, CO2, and several polycarboxylic acids were formed in all systems. The primary characteristics observed in the latter system were: (1) Higher yield of the decomposition of aceticacid; (2) Lower yield of the formation of polycarboxylic acids; (3) No effect on the formation of methane; (4) Higher yield of the formation of carbon dioxide; and (5) The reduction of Fe3+ in the octahedral sites of Na-montmorillonite. A possible reaction scheme was proposed to account for the observed changes. The results are important in understanding heterogeneous processes in radiation catalysis and might be significant to prebiotic chemistry.

Acetate kinase (ACK) converts acetyl phosphate to acetate along with the generation of ATP in the pathway for mixed-acid fermentation in Lactococcus lactis. The reverse reaction yields acetyl phosphate for assimilation purposes. Remarkably, L. lactis has two ACK isozymes, and the corresponding genes are present in an operon. We purified both enzymes (AckA1 and AckA2) from L. lactis MG1363 and determined their oligomeric state, specific activities, and allosteric regulation. Both proteins form homodimeric complexes, as shown by size exclusion chromatography and static light-scattering measurements. The turnover number of AckA1 is about an order of magnitude higher than that of AckA2 for the reaction in either direction. The Km values for acetyl phosphate, ATP, and ADP are similar for both enzymes. However, AckA2 has a higher affinity for acetate than does AckA1, suggesting an important role under acetate-limiting conditions despite the lower activity. Fructose-1,6-bisphosphate, glyceraldehyde-3-phosphate, and phospho-enol-pyruvate inhibit the activities of AckA1 and AckA2 to different extents. The allosteric regulation of AckA1 and AckA2 and the pool sizes of the glycolytic intermediates are consistent with a switch from homolactic to mixed-acid fermentation upon slowing of the growth rate. PMID:24464460

Monocolonization of germ-free (GF) mice enables the study of specific bacterial species in vivo. Lactobacillus acidophilus NCFMTM (NCFM) is a probiotic strain; however, many of the mechanisms behind its health-promoting effect remain unknown. Here, we studied the effects of NCFM on the metabolome of jejunum, cecum, and colon of NCFM monocolonized (MC) and GF mice using liquid chromatography coupled to mass-spectrometry (LC-MS). The study adds to existing evidence that NCFM in vivo affects the bile acid signature of mice, in particular by deconjugation. Furthermore, we confirmed that carbohydrate metabolism is affected by NCFM in the mouse intestine as especially the digestion of oligosaccharides (penta- and tetrasaccharides) was increased in MC mice. Additionally, levels of ?-tocopherol acetate (vitamin E acetate) were higher in the intestine of GF mice than in MC mice, suggesting that NCFM affects the vitamin E acetate metabolism. NCFM did not digest vitamin E acetate in vitro, suggesting that direct bacterial metabolism was not the cause of the altered metabolome in vivo. Taken together, our results suggest that NCFM affects intestinal carbohydrate metabolism, bile acid metabolism and vitamin E metabolism, although it remains to be investigated whether this effect is unique to NCFM. PMID:24717228

Cuttings of pea (Pisum sativum L. cv Marma) were treated with 1-aminocyclopropane-l-carboxylic acid (ACC). This treatment caused increased ethylene production and reduction of root formation. The effect of 0.1 mM ACC on the level of endogenous indole-3-aceticacid (IAA) in the rooting zone and in the shoot apex was analyzed by gas chromatography-single ion monitoring mass spectrometry or by high

Formic and aceticacids are ubiquitous in the environment and in many biological processes. Analysis of the stable carbon isotope composition (?(13)C) of formic and aceticacids is important to understanding their biogeochemical cycles. However, it has been faced with poor accuracy and high detection limits due to their low carbon number, high hydrophilicity, and semi-volatility. Here we developed an analytical technique by needle trap and gas chromatography-isotope ratio mass spectrometry (GC-IRMS). The organic acids in aqueous solution were extracted using a NeedlEx needle through purge-and-trap and were analyzed by GC-IRMS for ?(13)C. The procedures incur no isotope fractionation. Defined as the point at which the mean ?(13)C is statistically the same as the given value and the analytical error starts rising, the method's detection limits are 200 and 100 mg/L for formic and aceticacids, respectively, with an uncertainty of approximately 0.5‰ in direct extraction and analysis. They were lowered to 1 mg/L with precision of 0.9‰ after samples were subjected to preconcentration. The method was successfully applied to natural samples as diverse as precipitation, vinegars, ant plasma, and vehicle exhaust, which vary considerably in concentration and matrix of the organic acids. It is applicable to the organic acids in not only aqueous solution but also gaseous phase. PMID:23395975

Stem applications of indole-3-aceticacid (IAA) or gibberellic acid (GA) did not prevent or alter tumor or teratoma formation in debudded tobacco plants (Nicotiana tabacum L., var. One Sucker). The materials produced intense (in case of GA) and moderate (in case of IAA) stem proliferations when applied to debudded plants but were without effect on intact plants. The results suggest that debudding-tumors are probably not related to or a result of an auxin or gibberellin deficit and that total debudding has a marked physiological effect on the plant. The altered physiological condition of the debudded plant, indicated by its responses to IAA and GA, may likely be related to tumor and teratoma formation. Images PMID:16656754

Pervaporation is a potential process for recovering bioethanol produced from biomass fermentation. Fermentation broths contain ethanol, water, and a variety of other compounds, often including carboxylic acids. The effects of aceticacid on long-term pervaporation of aqueous et...

This monograph on norethisterone and its acetate (NOR) includes chemical and physical data (synonyms and trade names), structural and molecular formulae and molecular weight of NOR, chemical and physical properties of NOR, and the production, use, occurrence, and analysis of NOR. Production of NOR and its acetate, both of which are not known to occur naturally, occurs via conversion of estrone to its methyl ester which is reduced to estradiol 3-methyl ether with lithium aluminum hydride; NOR acetate is synthesized by acetylating NOR with acetic anhydride in pyridine. NOR has been used for human medicine in a variety of ways: 1) to treat amenorrhea, 2) to treat dysfunctional uterine bleeding, and 3) for treating endometriosis. It has also been used to treat premenstrual tension and dysmenorrhea. Medicinal use of NOR acetate is similar to that for NOR. Analytical procedures for determining NOR as a bulk chemical are presented tabularly. Biological data relevant to the evaluation of carcinogenic risk to humans are presented briefly. With experimental animals, when administered alone NOR and/or its acetate increased the incidence of benign liver tumors in male mice and of pituitary tumors in females; females also suffered granulosa-cell ovarian tumors. NOR in combination with an estrogen increased incidence of pituitary tumors in mice of both sexes. NOR is embryolethal in some species and produces virilization in female fetuses. It is concluded that there is limited evidence for the carcinogenicity of NOR and its acetate in animals. Human studies are not available, but NOR is implicated causally as a progestogenic element in side effects of combined oral contraceptive usage. PMID:120838

Selective removal of aceticacid from simulated hemicellulosic hydrolysates containing xylose and sulfuric acid was attempted in a batch emulsion liquid membrane (ELM) system with organophosphorus extractants. Various experimental variables were used to develop a more energy-efficient ELM process. Total operation time of an ELM run with a very small quantity of trioctylphosphine oxide as the extractant was reduced to about a third of those required to attain almost the same extraction efficiency as obtained in previous ELM works without any extractant. Under specific conditions, aceticacid was selectively separated with a high degree of extraction and insignificant loss of xylose, and its purity and enrichment ratio in the stripping phase were higher than 92% and 6, respectively. Also, reused organic membrane solutions exhibited the extraction efficiency as high as fresh organic solutions did. These results showed that the current ELM process would be quite practical. PMID:26056774

Objective: Gastric ulcer is an important clinical problem, chiefly due to extensive use of some drugs. The aim was to assess the activity of Mumijo extract (which is used in traditional medicine) against aceticacid induced gastric ulcer in rats. Materials and Methods: The aqueous extract of Mumijo was prepared. Animals were randomly (n = 10) divided into four groups: Control, sham-operated group (received 0.2 ml of aceticacid to induce gastric ulcer), Mumijo (100 mg/kg/daily) were given for 4 days postacetic acid administration, and ranitidine group (20 mg/kg). The assessed parameters were pH and pepsin levels (by Anson method) of gastric contents and gastric histopathology. Ranitidine was used as reference anti-ulcer drug. Results: The extract (100 mg/kg/daily, p.o.) inhibited acidacetic-induced gastric ulceration by elevating its pH versus sham group (P < 0.01) and decreasing the pepsin levels compared to standard drug, ranitidine (P < 0.05). The histopathology data showed that the treatment with Mumijo extract had a significant protection against all mucosal damages. Conclusion: Mumijo extract has potent antiulcer activity. Its anti-ulcer property probably acts via a reduction in gastric acid secretion and pepsin levels. The obtained results support the use of this herbal material in folk medicine. PMID:25709338

of acetone, acetaldehyde, and aceticacid at 243 nm: translational energy releases in the H atom channel, acetaldehyde, and aceticacid at 243 nm have been investigated by detecting H atoms using two photon absorption- sociation of acetone, acetaldehyde, and aceticacid at 243 nm have been investigated. At 243 nm, one photon

A polymer electrolyte membrane (PEM) reactor is described for use in Kolbe electrolysis: the anodic oxidation of an alkyl carboxylic acid with subsequent decarboxylation and coupling to yield a dimer, 2RCOOH {r_arrow} R-R + 2CO{sub 2} + 2e{sup {minus}} + 2H{sup +}. Platinized Nafion 117 is the PEM and functions simultaneously as the electrolyte and separator. Results demonstrating the feasibility of Kolbe electrolysis in a PEM reactor are presented for the oxidation of gaseous aceticacid (in a nitrogen diluent) to ethane and carbon dioxide, with hydrogen evolution at the counter electrode. The investigation includes the following effects on current density, current efficiency, and product selectivity: aceticacid partial pressure (P{sub total} {approx} 1 atm), cell voltage and temperature, phase of the catholyte (liquid water or humidified nitrogen), and the procedure used to prepare the membrane-electrode assembly. Current densities from 0.06 to 0.4 A/cm{sup 2} with Kolbe current efficiencies of 10 to 90% were obtained for cell voltages ranging from 4 to 10 V. The best results were obtained using PEMs platinized by a nonequilibrium impregnation-reduction method; a 75% current efficiency at 0.3 A/cm{sup 1} with a cell voltage of 6 V were measured at the following reaction conditions: 42 C reactor, 58 mm Hg aceticacid (50 C aceticacid dew point), and 42 C liquid water to the cathode. These initial results are encouraging for Kolbe electrolysis in a PEM cell; additional work, however, is needed to determine if the PEM strategy may be employed using a liquid-phase reactant. In addition, optimal reaction conditions and downstream mass-transfer separation requirements remain to be determined, both of which are reactant specific.

Lignin in kraft pulp was extracted by enzymatic hydrolysis of the carbohydrates, acidolysis with dioxane-water-HCl (conventional method), and acidolysis with aceticacid-water-ZnCl2. The latter method was shown to extract lignin with a better yield than for conventional acidolysis and with a much lower content in impurities than for enzymatic hydrolysis. It was confirmed by 13C NMR analysis of the lignin samples that conventional hydrolysis modified the lignin polymer, causing the cleavage of some aryl-ether linkages. The cleavage was also observed on a model compound submitted to the same extraction conditions. In that respect, the aceticacid-water-ZnCl2 method was less damaging and consequently more suitable for analytical purposes. PMID:15587082

In glacial aceticacid, phthalanilic acid and its monosubstituents are known to be converted to the corresponding phthalimides in relatively good yields. In this study, we computationally investigated the experimentally proposed two-step (addition-elimination or cyclization-dehydration) mechanism at the second-order Møller-Plesset perturbation (MP2) level of theory for the unsubstituted phthalanilic acid, with an explicit aceticacid molecule included in the calculations. In the first step, a gem-diol tetrahedral intermediate is formed by the nucleophilic attack of the amide nitrogen. The second step is dehydration of the intermediate to give N-phenylphthalimide. In agreement with experimental findings, the second step has been shown to be rate-determining. Most importantly, both of the steps are catalyzed by an aceticacid molecule, which acts both as proton donor and acceptor. The present findings, along with those from our previous studies, suggest that aceticacid and other carboxylic acids (in their undissociated forms) can catalyze intramolecular nucleophilic attacks by amide nitrogens and breakdown of the resulting tetrahedral intermediates, acting simultaneously as proton donor and acceptor. In other words, double proton transfers involving a carboxylic acid molecule can be part of an extensive bond reorganization process from cyclic hydrogen-bonded complexes. PMID:26030675

2-Hydroxy-2-(ethoxyphenylphosphinyl)aceticacid, a new type of organophosphorus compound possessing two stereogenic centers, was investigated. Racemic 2-butyryloxy-2-(ethoxyphenylphosphinyl)aceticacid was synthesized and hydrolyzed using four bacterial species as biocatalysts. In all cases the reaction was more or less stereoselective and isomers bearing a phosphorus atom with an (SP)-configuration were hydrolyzed preferentially. The observed (1)H and (31)P NMR chemical shifts of Mosher esters of 2-hydroxy-2-(ethoxyphenylphosphinyl)aceticacid were correlated with the configurations of both stereogenic centers of all four stereoisomers. PMID:26069926

A 15-year-old female soccer player presented with chronic plantar fasciitis. She was treated with aceticacid iontophoresis and a combination of rehabilitation protocols, ultrasound, athletic taping, custom orthotics and soft tissue therapies with symptom resolution and return to full activities within a period of 6 weeks. She reported no significant return of symptoms post follow-up at 2 months. Aceticacid iontophoresis has shown promising results and further studies should be considered to determine clinical effectiveness. The combination of aceticacid iontophoresis with conservative treatments may promote recovery within a shorter duration compared to the use of one-method treatment approaches. PMID:17885679

Auxin is a pivotal plant hormone that regulates many aspects of plant growth and development. Auxin signaling is also known to promote plant disease caused by plant pathogens. However, the mechanism by which this hormone confers susceptibility to pathogens is not well understood. Here, we present evidence that fungal and bacterial plant pathogens hijack the host auxin metabolism in Arabidopsis thaliana, leading to the accumulation of a conjugated form of the hormone, indole-3-aceticacid (IAA)-Asp, to promote disease development. We also show that IAA-Asp increases pathogen progression in the plant by regulating the transcription of virulence genes. These data highlight a novel mechanism to promote plant susceptibility to pathogens through auxin conjugation. PMID:22374398

In this study we investigated bleomycin-induced pulmonary toxicity in patients with germ-cell tumour by means of technetium-99m diethylene triamine penta-aceticacid aerosol scintigraphy. Twenty untreated patients who had no clinical or radiological evidence of pulmonary disease received four courses of etoposide, cisplatin and bleomycin chemotherapy. Aerosol lung scintigraphy and pulmonary function tests were performed in all patients before bleomycin treatment

The steady-state performance of a recycle two-stage fermentor with cell separators after each stage is studied numerically for continuous production of aceticacid. This system has two fresh-medium feed streams and the bleed withdrawn from the first stage is supplied to the second fermentor for utilization of the high cell concentration in the bleed. Kinetic expressions and parameter values are

Furfural and aceticacid from lignocellulosic hydrolysates are the prevalent inhibitors to Zymomonas mobilis during cellulosic ethanol production. Developing a strain tolerant to furfural or aceticacid inhibitors is difficul by using rational engineering strategies due to poor understanding of their underlying molecular mechanisms. In this study, strategy of adaptive laboratory evolution (ALE) was used for development of a furfural and aceticacid-tolerant strain. After three round evolution, four evolved mutants (ZMA7-2, ZMA7-3, ZMF3-2, and ZMF3-3) that showed higher growth capacity were successfully obtained via ALE method. Based on the results of profiling of cell growth, glucose utilization, ethanol yield, and activity of key enzymes, two desired strains, ZMA7-2 and ZMF3-3, were achieved, which showed higher tolerance under 7 g/l aceticacid and 3 g/l furfural stress condition. Especially, it is the first report of Z. mobilis strain that could tolerate higher furfural. The best strain, Z. mobilis ZMF3-3, has showed 94.84 % theoretical ethanol yield under 3-g/l furfural stress condition, and the theoretical ethanol yield of ZM4 is only 9.89 %. Our study also demonstrated that ALE method might also be used as a powerful metabolic engineering tool for metabolic engineering in Z. mobilis. Furthermore, the two best strains could be used as novel host for further metabolic engineering in cellulosic ethanol or future biorefinery. Importantly, the two strains may also be used as novel-tolerant model organisms for the genetic mechanism on the "omics" level, which will provide some useful information for inverse metabolic engineering. PMID:25935346

To solve the blockage caused by silica during the hydrothermal conversion of rice hulls into aceticacid in a continuous-flow reactor, the removal of silica from rice hulls and the retainment of organics by alkaline extraction were carried out in a range of pH values from 5 to 12 and temperatures from 30 to 85°C. It was found that the

Flavone aceticacid (FAA, NSC 347512) is known to selectively reduce tumor blood flow. Taking advantage of this pharmacodynamic\\u000a effect, we have previously shown that FAA in combination with hyperthermia (HT) can produce a marked improvement in antitumor\\u000a response in mice. In the present study, we investigated whether FAA could increase the cytotoxicity of mitomycin C (MMC),\\u000a a bioreductive drug

Using Caenorhabditis elegans as a model organism, various natural substances and commercial health-food supplements were screened to evaluate their effects on longevity. Among the substances tested, aceticacid and Reishi polysaccharide fraction 3 (RF3) were shown to increase the expression of the lifespan and longevity-related transcription factor DAF-16 in C. elegans. We have shown that RF3 activates DAF-16 expression via

The effect of the herbicide 2,4-Dichlorophenoxy aceticacid generally used in agriculture was studied on the nitrogen fixing blue-green alga Cylindrospermum sp. The alga could tolerate up to 150 µg per ml in liquid culture and 100 µg per ml on agar plates without any inhibitory effect on growth and survival. The maximum tolerance was up to 800 µg per

A method and apparatus are disclosed for converting waste gases from industrial processes such as oil refining, carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various organic acids or alcohols by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified. In an exemplary recovery process, the bioreactor raffinate is passed through an extraction chamber into which one or more non-inhibitory solvents are simultaneously introduced to extract the product. Then, the product is separated from the solvent by distillation. Gas conversion rates can be maximized by use of centrifuges, hollow fiber membranes, or other means of ultrafiltration to return entrained anaerobic bacteria from the bioreactor raffinate to the bioreactor itself, thus insuring the highest possible cell concentration. 4 figs.

A method and apparatus for converting waste gases from industrial processes such as oil refining, carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various organic acids or alcohols by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified. In an exemplary recovery process, the bioreactor raffinate is passed through an extraction chamber into which one or more non-inhibitory solvents are simultaneously introduced to extract the product. Then, the product is separated from the solvent by distillation. Gas conversion rates can be maximized by use of centrifuges, hollow fiber membranes, or other means of ultrafiltration to return entrained anaerobic bacteria from the bioreactor raffinate to the bioreactor itself, thus insuring the highest possible cell concentration.

The objective of this experimental study was to discover volatile metabolites present in exhaled breath that could be used as biomarkers of gastro-esophageal reflux disease, GERD, one of the most common causes of chronic cough. An in vitro model based on pork tissue samples exposed to a challenge by artificial gastric fluid was used to identify specific volatile compounds to be chosen for quantification in directly exhaled breath of GERD patients and controls using selected ion flow tube mass spectrometry, SIFT-MS. GC/MS analyses of the headspace of this in vitro model indicated that the only volatile compound significantly increased was aceticacid. End expiratory concentration of aceticacid measured by SIFT-MS in mouth exhaled breath of 22 GERD patients (median 85 ppbv) was found to be significantly higher than that in breath of a control group (median 48 ppbv). Breath aceticacid may be useful for non-invasive diagnostics of GERD and other conditions resulting in the lowering of pH of the lining of the airways. PMID:25189108

Various culture media have been proposed for the isolation and selective enumeration of bifidobacteria. Mupirocin is widely used as a selective factor along with glacial aceticacid. TOS (transgalactosylated oligosaccharides) medium supplemented with mupirocin is recommended by the International Dairy Federation for the detection of bifidobacteria in fermented milk products. Mupirocin media with aceticacid are also reliable for intestinal samples in which bifidobacteria predominate. However, for complex samples containing more diverse microbiota, the selectivity of mupirocin media is limited. Resistance to mupirocin has been demonstrated by many anaerobic bacteria, especially clostridia. The objective was to identify an antibiotic that inhibits the growth of clostridia and allows the growth of bifidobacteria, and to use the identified substance to develop a selective cultivation medium for bifidobacteria. The susceptibility of bifidobacteria and clostridia to 12 antibiotics was tested on agar using the disk diffusion method. Only norfloxacin inhibited the growth of clostridia and did not affect the growth of bifidobacteria. Using both pure cultures and faecal samples from infants, adults, calves, lambs, and piglets, the optimal concentration of norfloxacin in solid cultivation media was determined to be 200 mg/L. Our results showed that solid medium containing norfloxacin (200 mg/L) in combination with mupirocin (100 mg/L) and glacial aceticacid (1 mL/L) is suitable for the enumeration and isolation of bifidobacteria from faecal samples of different origins. PMID:25865525

The effects of six water-soluble vitamins on tryptophan-dependent synthesis of indole-3-aceticacid in Azospirillum brasilense were investigated. A multifactorial regression analysis was employed to produce models of indole-3-aceticacid synthesis versus concentrations of tryptophan and the vitamins added to the growth medium. Very low levels of the B-group vitamins added at 10 to 100 microg l(-1) affected production of indole-3-aceticacid in A. brasilense. The largest release of this phytohormone was observed after amendment with pyridoxine and nicotinic acid. Results of the study suggest a role these vitamins may fulfil in the regulation of indole-3-aceticacid synthesis in A. brasilense. PMID:11061189

It is assumed that theophylline (THEO) and its xanthinic derivatives inhibit lung phosphodiesterase (PDE) and block adenosine receptors in the induction of bronchodilatation. Since the theophyllinic compound ambroxol-theophylline-7-aceticacid (ATA) has been shown in vivo to be a sound bronchodilator, this paper compares the action of ambroxol-theophylline-7-acetate (ATA), its two components, theophylline-7-aceticacid (TAA) and ambroxol (AMB), and theophylline (THEO) on the hydrolytic activity of three rat-lung cAMP PDE (types I, III and IV) and on striatal adenosine receptors. THEO inhibited all three isoenzymes with equal intensity, whereas ATA was as powerful but inhibited types III and IV only, on which AMB and TAA also showed lower effects. Lastly, unlike THEO, ATA and its two components were unable to antagonize adenosine receptors. Taken as a whole, these results suggest that the bronchodilating activity of ATA is the result of specific inhibition of particular forms of PDE and is thus more specific than that of THEO alone. PMID:1328102

Conclusions 1.Formation of a peroxy ester from tert-butyl hydroperoxide and caproic acid proceeds through rupture of the H-OO bond.2.Rate constants for the formation of peroxy exters from tert-butyl hydroperoxide and acetic and caproic acids in the presence of mineral acids have been determined as a function of the acidity. These relations are explained in terms of the limiting step in

CdO thin films were deposited on glass substrates from cadmium acetate dihydrate along with precursor additives, aceticacid and CTAB using home built splay pyrolysis unit. XRD studies imply that the CdO thin films to be preferably oriented in the (1 1 1) plane. The Williamson-Hall plot indicates the presence of microstrain, especially high with aceticacid additive. Surface morphology was found to be closely packed spherical crystallite with precursor additives. Optical studies reveal a considerable change in the transmittance and band gap. Peak position is shifted in the Raman spectra, due to precursor additives.

A strain development program was initiated to improve the tolerance of the pentose-fermenting yeast Pachysolen tannophilus to inhibitors in lignocellulosic hydrolysates. Several rounds of UV mutagenesis followed by screening were used to select for mutants of P. tannophilus NRRL Y2460 with improved tolerance to hardwood spent sulfite liquor (HW SSL) and aceticacid in separate selection lines. The wild type (WT) strain grew in 50 % (v/v) HW SSL while third round HW SSL mutants (designated UHW301, UHW302 and UHW303) grew in 60 % (v/v) HW SSL, with two of these isolates (UHW302 and UHW303) being viable and growing, respectively, in 70 % (v/v) HW SSL. In defined liquid media containing aceticacid, the WT strain grew in 0.70 % (w/v) aceticacid, while third round aceticacid mutants (designated UAA301, UAA302 and UAA303) grew in 0.80 % (w/v) aceticacid, with one isolate (UAA302) growing in 0.90 % (w/v) aceticacid. Cross-tolerance of HW SSL-tolerant mutants to aceticacid and vice versa was observed with UHW303 able to grow in 0.90 % (w/v) aceticacid and UAA302 growing in 60 % (v/v) HW SSL. The UV-induced mutants retained the ability to ferment glucose and xylose to ethanol in defined media. These mutants of P. tannophilus are of considerable interest for bioconversion of the sugars in lignocellulosic hydrolysates to ethanol. PMID:24122119

2-(N,N-dimethylamino) benzylidene imino-4-(4-methyl phenyl)-1,3-thiazole (DIMPT), 2-benzylidene imino-4-(4-methyl phenyl)-1,3-thiazole (BIMPT), 2-salicylidene imino-4-(4-methyl phenyl)-1,3-thiazole (SIMPT) and 2-cinnamylidene imino-4-(4-methyl phenyl)-1,3-thiazole (CIMPT) were synthesized in the laboratory and their influence on the inhibition of corrosion of mild steel in 20 formic acid and 20 aceticacid was investigated by weight loss and potentiodynamic polarization techniques. The inhibition efficiency of these compounds was found to

Ulipristal acetate, a selective progesterone-receptor modulator, inhibits the proliferation and induces apoptosis of leiomyoma cells in vitro. It also modulates the expression of vascular endothelial growth factors and hormone receptors and modulates extracellular matrix breakdown in leiomyoma cells but not in myometrial cells. In two randomized, double-blind, multinational phase III trials of 13 weeks' duration in women aged 18-50 years with uterine fibroids, a once-daily regimen of oral ulipristal acetate 5 mg/day controlled excessive uterine bleeding (primary endpoint) in ?90% of patients. Ulipristal acetate 5 mg/day was more effective than placebo and was shown to be noninferior to intramuscular leuprolide acetate 3.75 mg once monthly in controlling uterine bleeding. Uterine bleeding was rapidly controlled by ulipristal acetate. Approximately half of recipients of ulipristal acetate 5 mg/day became amenorrhoeic within the first 10 days of treatment. Furthermore, uterine bleeding was controlled significantly more rapidly for recipients of ulipristal acetate than recipients of leuprolide acetate. A significantly greater median reduction from baseline in total fibroid volume was observed for recipients of ulipristal acetate 5 mg once daily than recipients of placebo following 13 weeks' treatment (coprimary endpoint). For patients who did not undergo surgery, the volume reduction was maintained for at least 6 months after discontinuing treatment. Ulipristal acetate was generally well tolerated in women with uterine fibroids. The incidence of hot flush occurred with a significantly lower frequency for recipients of ulipristal acetate than for recipients of leuprolide acetate. PMID:22568731

A general gas chromatography/mass spectrometry (MS)-based screen was performed to identify catabolites and conjugates of indole-3-aceticacid (IAA) during vegetative growth of Arabidopsis. This experiment revealed the existence of two new conjugates: N-(indole-3-acetyl)-alfa-alanine (IA-Ala) and N-(indole-3-acetyl)-alfa-leucine (IA-Leu). A method for quantitative analysis of IAA metabolites in plant extracts by liquid chromatography-electrospray tandem MS has been developed. The accuracy and precision of the new method are better than 10% for standards close to the detection limit, and are between 6% and 16% for the entire protocol applied to plant extracts. The low detection limits, 0.02 to 0.1 pmol for the different metabolites, made it possible to use as little as 50 to 100 mg of tissue for quantitative analysis. The analysis was performed on different tissues of an Arabidopsis plant at two stages of development, using heavy labeled internal standards of the catabolite 2-oxoindole-3-aceticacid as well as IAA conjugated to amino acids: aspartate, glutamate, Ala, and Leu. Expanding leaves and roots that generally contain high amounts of the free hormone also contained the highest levels of IA-aspartate, IA-glutamate, and 2-oxoindole-3-aceticacid, supporting their role as irreversible catabolic products. The levels of IA-Leu and IA-Ala did not follow the general distribution of IAA. Interestingly, the level of IA-Leu was highest in roots and IA-Ala in the aerial tissues. PMID:11743128

Acetate is the precursor of approximately two-thirds of the methane produced by anaerobic bioreactors and many other methanogenic habitats. Besides their intrinsic interest, thermophilic acetotrophic methanogenic cultures usually grow at least twice as fast as their mesophilic counterparts, making them more amenable to study. In recent years, attention has been mainly focused on the thermophilic acetate utilizing methanogen Methanothrix strain CALS-1. Methanothrix, also called Methanosaeta, is one of only two methanogenic genera known to convert acetate to methane, the other being Methanosarcina. The faster-growing more versatile Methanosarcina has been better studied. However, when one examines anaerobic digestor contents, Methanothrix is often the dominant acetate-utilizing methanogen. As described in previous progress reports, the authors have achieved methanogenesis from acetate in cell-free extracts of Methanothrix strain CALS-1 grown in a pH auxostat. Using these cell extracts, specific activities for methanogenesis from acetate and ATP of 100--300 nmol/min were routinely obtained, levels comparable to the rate in whole cells, which is not usually the case in methanogenic extracts. Recently obtained results are given and discussed for the following: Methanogenesis in crude extracts; Role of the cell membrane in methanogenesis from acetate; Carbon monoxide dehydrogenase; Novel thermophilic cultures converting acetate to methane; and Methanol-utilizing methanogen.

Aceticacid is the main component of the volatile acidity of grape musts and wines. It can be formed as a by-product of alcoholic\\u000a fermentation or as a product of the metabolism of acetic and lactic acid bacteria, which can metabolize residual sugars to\\u000a increase volatile acidity. Aceticacid has a negative impact on yeast fermentative performance and affects the

Traditionally, schemes depicting auxin biosynthesis in plants have been notoriously complex. They have involved up to four possible pathways by which the amino acid tryptophan might be converted to the main active auxin, indole-3-aceticacid (IAA), while another pathway was suggested to bypass tryptophan altogether. It was also postulated that different plants use different pathways, further adding to the complexity. In 2011, however, it was suggested that one of the four tryptophan-dependent pathways, via indole-3-pyruvic acid (IPyA), is the main pathway in Arabidopsis thaliana, although concurrent operation of one or more other pathways has not been excluded. We recently showed that, for seeds of Pisum sativum (pea), it is possible to go one step further. Our new evidence indicates that the IPyA pathway is the only tryptophan-dependent IAA synthesis pathway operating in pea seeds. We also demonstrated that the main auxin in developing pea seeds, 4-chloroindole-3-aceticacid (4-Cl-IAA), which accumulates to levels far exceeding those of IAA, is synthesized via a chlorinated version of the IPyA pathway. PMID:23073010

Saccharococcus sacchari is the primary colonizer of the developing “sterile” tissue between the leaf sheath and stem of sugar cane. The honeydew secreted by the mealybugs is acidic (about pH 3) and supports an atypical epiphytic microbiota dominated by acetobacter-like bacteria and acidophilic yeast species. However, Erwinia and Leuconostoc species predominate within the leaf sheath pocket region when the mealybugs die out. The unidentified acetobacters were readily isolated from S. sacchari throughout its life cycle and from other genera of mealybugs on sugar cane and various other plants, both above and below ground. No other insect present on sugar cane was a significant vector of aceticacid bacteria. The major factors restricting microbial diversity within the environs of mealybugs were considered to be yeast activity along with bacterial production of aceticacid, ketogluconic acids, and gamma-pyrones, in association with their lowering of pH. The microbial products may aid in suppressing the attack by the parasitic mold Aspergillus parasiticus on mealybugs but could act as attractants for the predatory fruit fly Cacoxenus perspicax. PMID:16348144

Atmospheric gas-phase and aqueous-phase (dew and fog) formic and aceticacids were measured over a cloud forest in Venezuela. The gaseous acids showed diurnal cycles, with higher mixing ratios during daytime. Higher concentrations were observed during the dry season (HCOOH 1.7 +/-0.5 ppb; CH 3COOH 1.4+/-0.6 ppb) in comparison with the rainy season (HCOOH 0.79+/-0.24 ppb; CH 3COOH 0.54+/-0.20 ppb). Liquid-phase concentrations in dew and fog are of the same order and range from 8.1 to 69.5 ?M for HCOOH and 4.3 to 15.3 ?M for CH 3COOH. The field-observed Henry's Law coefficients, calculated from the simultaneous measurements of gas- and liquid-phase acids, do not show a significant trend with the pH of the solution, in contrast to theoretical considerations. Dry deposition velocities to the nighttime dew are 1.1+/-0.6 and 0.68+/-0.42 cm s -1 for formic and aceticacids, respectively. A loss of 0.054 ppb HCOOH and 0.022 ppb CH 3COOH from the atmospheric boundary layer to the dew is produced nightly.

Development of lymphoceles after renal transplantation is a well-described complication that occurs in up to 40% of recipients. The gold standard approach for the treatment of symptomatic cases is not well defined yet. Management options include simple aspiration, marsupialization by a laparotomy or laparoscopy, and percutaneous sclerotherapy using different chemical agents. Those approaches can be associated, and they depend on type, dimension, and localization of the lymphocele. Percutaneous sclerotherapy is considered to be less invasive than the surgical approach; it can be used safely and effectively, with low morbidity, in huge, rapidly accumulating lymphoceles. Moreover, this approach is highly successful, and the complication rate is acceptable; the major drawback is a recurrence rate close to 20%. We herewith report a renal transplant case in which the patient developed a symptomatic lymphocele that was initially treated by ultrasound-guided percutaneous sclerotherapy with ethanol and thereafter using aceticacid for early recurrence. A few hours after injection of aceticacid in the lymphatic cavity, the patient started to complain of acute pain localized to the renal graft and fever. An ultrasound of the abdomen revealed thrombosis of the renal vein and artery. The patient was immediately taken to the operating room, where the diagnosis of vascular thrombosis was confirmed and the graft was urgently explanted. In conclusion, we strongly suggest avoiding the use of aceticacid as a slerosating agent for the percutaneous treatment of post-renal transplant lymphocele because, based on our experience, it could be complicated by vascular thrombosis of the kidney, ending in graft loss.

6061 Al-SiCpcomposite was solutionizedat 350 °C for 30 minutes and water quenched. It was then underaged at 140 °C (T6 treatment). The aging behaviour of the composite was studied using Rockwell B hardness measurement. Corrosion behaviour of the underaged sample was studied in different concentrations of aceticacid and at different temperatures. Benzimidazole at different concentrations was used for the inhibition studies. Inhibition efficiency of benzimidazole was calculated for different experimental conditions. Thermodynamic parameters were found out which suggested benzimidazole is an efficient inhibitor and it adsorbed on to the surface of composite by mixed adsorption where chemisorption is predominant.

The thermo-oxidative stability of aceticacid lignin-containing polyurethane (LPU) that contains cross-linking agents, such\\u000a as 1-aminopropyltriethoxy-silane (APTS) and\\/or trimethylolpropane (TMP) was investigated based on the thermogravimetric analysis\\u000a (TGA) method, their kinetic parameters in the thermo-oxidative process was determined. FT-IR certified the occurrence of interaction\\u000a between lignin and polyurethane (PU). It was found that continuous membrane can be formed when lignin

The title compound, C10H11N3O4·C2H4O2, was prepared by an electrochemical technique. In the crystal, aceticacid mol­ecules are involved in hydrogen bonding to two separate propano­ylurea mol­ecules, acting as a donor in an O—H?O inter­action and as an acceptor in two N—H?O inter­actions. The propano­ylurea mol­ecules inter­act with each other via N—H?O hydrogen bonds. C—H?O inter­actions also stabilize the crystal structure. PMID:22219927

Summary The influence of operating conditions (temperature, HCl catalyst concentration and time) on the percentage of xylose solubilized\\u000a in the acid-catalysed delignification of Eucalyptus globulus wood by aceticacid was studied using an incomplete 3 3 3\\u000a factorial design. Regression analysis afforded an equation satisfactorily correlating the experimental results. A kinetic\\u000a model of polysaccharide hydrolysis is proposed which involves two parallel

Received 23 August 2004\\/Accepted 28 October 2004 An antimicrobial compound was isolated from Azospirillum brasilense culture extracts by high-performance liquid chromatography and further identified by gas chromatography-mass spectrometry as the auxin-like molecule, phenylacetic acid (PAA). PAA synthesis was found to be mediated by the indole-3-pyruvate decar- boxylase, previously identified as a key enzyme in indole-3-aceticacid (IAA) production in A.

Biomass is a renewable energy resource that can be converted into liquid fuel suitable for transportation applications. As a widely available biomass form, lignocellulosic biomass can have a major impact on domestic transportation fuel supplies and thus help meet the Energy Independence and Security Act renewable energy goals (U.S. Congress 2007). This study performs a techno-economic analysis of the thermo chemical conversion of biomass to ethanol, through methanol and aceticacid, followed by hydrogenation of aceticacid to ethanol. The conversion of syngas to methanol and methanol to aceticacid are well-proven technologies with high conversions and yields. This study was undertaken to determine if this highly selective route to ethanol could provide an already established economically attractive route to ethanol. The feedstock was assumed to be wood chips at 2000 metric ton/day (dry basis). Two types of gasification technologies were evaluated: an indirectly-heated gasifier and a directly-heated oxygen-blown gasifier. Process models were developed and a cost analysis was performed. The carbon monoxide used for aceticacid synthesis from methanol and the hydrogen used for hydrogenation were assumed to be purchased and not derived from the gasifier. Analysis results show that ethanol selling prices are estimated to be $2.79/gallon and $2.81/gallon for the indirectly-heated gasifier and the directly-heated gasifier systems, respectively (1stQ 2008$, 10% ROI). These costs are above the ethanol market price for during the same time period ($1.50 - $2.50/gal). The co-production of aceticacid greatly improves the process economics as shown in the figure below. Here, 20% of the aceticacid is diverted from ethanol production and assumed to be sold as a co-product at the prevailing market prices ($0.40 - $0.60/lb aceticacid), resulting in competitive ethanol production costs.

Previous work has indicated that anatomical and morphological changes (stunting and dichotomy) in roots of various conifers may be influenced by plant-growth-regulating substances secreted by mycorrhizae. Indole-3-aceticacid (IAA) has been tentatively identified as a major auxin produced by some selected ectomycorrhizae. We report the isolation and detection of IAA as a secondary metabolite from Pisolithus tinctorius by thin-layer chromatography, high-performance liquid chromatography (HPLC), enzyme-linked immunosorbent (monoclonal antibody) assay (ELISA), and unequivocal identification by gas chromatography-mass spectrometry (GC-MS). The thin-layer chromatography methods for auxin isolation described here are novel, with the use of heptane-acetone-glacial aceticacid as the migrating solvent and formaldehyde, H2SO4, and vanadate in detection. The acidic extract of the culture supernatant was methylated with ethereal diazomethane to detect IAA as methyl-3-IAA by HPLC, ELISA, and GC-MS. The quantitative amount of IAA detected ranged from 4 to 5 ?mol liter?1 by HPLC and ELISA. Another unidentified metabolite was detected by GC-MS with a typical indole nucleus (m/z = 130), indicating that it could be an intermediate in auxin metabolism. Plant response (Pseudotsuga menziesii, Douglas fir) was monitored upon inoculation of P. tinctorius and l-tryptophan. There was a consistent increase in plant height and stem diameter as a result of the two treatments, with statistical differences in dry weights of the shoots and roots. Images PMID:16347506

Fragments from organic molecule dissociation (such as reactive ions and radicals) can form interstellar complex molecules like amino acids. The goal of this work is to experimentally study photoionization and photodissociation processes of aceticacid (CH$_3$COOH), a glycine (NH$_2$CH$_2$COOH) precursor molecule, by soft X-ray photons. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing soft X-ray photons from a toroidal grating monochromator (TGM) beamline (100 - 310 eV). Mass spectra were obtained using the photoelectron photoion coincidence (PEPICO) method. Kinetic energy distribution and abundances for each ionic fragment have been obtained from the analysis of the corresponding peak shapes in the mass spectra. Absolute photoionization and photodissociation cross sections were also determined. We have found, among the channels leading to ionization, that only 4-6% of CH$_3$COOH survive the strong ionization field. CH$_3$CO$^+$, COOH$^+$ and CH$_3^+$ ions are the main fragments, and the presence of the former may indicate that the production-destruction process of aceticacid in hot molecular cores (HMCs) could decrease the H$_2$O abundance since the net result of this process converts H$_2$O into OH + H$^+$. The COOH$^+$ ion plays an important role in ion-molecule reactions to form large biomolecules like glycine.

Background/Objectives Colonic fermentation of dietary fiber may improve insulin sensitivity via the metabolic effects of short chain fatty acids (SCFA) in reducing free fatty acids (FFA). The main objectives of this study were to compare peripheral uptake of acetate (AC) in participants with normal (< 40pmol/L, NI) and high (? 40pmol/L, HI) plasma-insulin and the ability of AC to reduce FFA in both groups. Subject/Methods Overnight fasted NI (n = 9) and HI (n = 9) participants were given an intravenous (IV) infusion of 140 mmol/L sodium acetate at 3 different rates over 90 minutes. The total amount of AC infused was 51.85 mmols. Results Acetate clearance in NI participants was not significantly different than that in HI participants (2.11 ± 0.23 vs 2.09 ± 0.24 ml/min). FFA fell in both groups, but rebounded to a greater extent in NI than HI participants (time × group interaction, P = 0.001). Significant correlations between insulin resistance (IR) indices (HOMA-IR, Matsuda and Insulinogenic Index) vs FFA rebound during IV AC infusion were also observed. Conclusions These findings suggest that AC uptake is similar in both groups. Participants with lower plasma insulin and lower IR indices had a greater FFA rebound. These results support the hypothesis that increasing AC concentrations in the systemic circulation may reduce lipolysis and plasma FFA concentrations and thus improve insulin sensitivity. More in-depth studies are needed to look at the effects of SCFA on FFA metabolism in insulin resistant participants. PMID:22828730

The electropolishing behavior of Inconel 718 alloy was studied in perchloric–aceticacid mixtures using a rotating disc electrode. The electropolishing behavior of an Inconel 718 weld, which was prepared with electron beam welding, was also investigated. A leveled but not brightened surface can be achieved when Inconel 718 alloy is potentiostatically polished in the acid mixture with 20vol.% perchloric acid.

Tetramethylammonium acetate (TMAAc) was found to be a selective reagent for the methylation of free acids. It was shown that free fatty acids and their salts could be fully derivatised by TMAAc in the presence of esterified fatty acids. This was performed on extracts containing mixtures of wood extractives and directly on pulps containing extractives. The alkaline reagent tetramethylammonium hydroxide

We report the rotational spectra of two conformers of the aceticacid-difluoroacetic acid adduct (CH3COOH-CHF2COOH) and supply information on its internal dynamics. The two conformers differ from each other, depending on the trans or gauche orientation of the terminal -CHF2 group. Both conformers display splittings of the rotational transitions, due to the internal rotation of the methyl group of aceticacid. The corresponding barriers are determined to be V3(trans)=99.8(3) and V3(gauche)=90.5(9) cm(-1) (where V3 is the methyl rotation barrier height). The gauche form displays a further doubling of the rotational transitions, due to the tunneling motion of the -CHF2 group between its two equivalent conformations. The corresponding B2 barrier is estimated to be 108(2) cm(-1). The increase in the distance between the two monomers upon OH?OD deuteration (the Ubbelohde effect) is determined. PMID:25056445

An analytical protocol for the isolation and quantification of indole-3-aceticacid (IAA) and its amino acid conjugates was developed. IAA is an important phytohormone and formation of its conjugates plays a crucial role in regulating IAA levels in plants. The developed protocol combines a highly specific immunoaffinity extraction with a sensitive and selective LC-MS/MS analysis. By using internal standards for each of the studied compounds, IAA and seven amino acid conjugates were analyzed in quantities of fresh plant material as low as 30 mg. In seeds of Helleborus niger, physiological levels of these compounds were found to range from 7.5 nmol g(-1) fresh weight (IAA) to 0.44 pmol g(-1) fresh weight (conjugate with Ala). To our knowledge, the identification of IAA conjugates with Gly, Phe and Val from higher plants is reported here for the first time. PMID:19836533

Ulcerative colitis is a common inflammatory bowel disease (IBD) of unknown etiology. Recent studies have revealed the role of some microorganisms in the initiation and perpetuation of IBD. The role of antibiotics in the possible modulation of colon inflammation is still uncertain. In this study, we evaluated the effects of two macrolides, namely azithromycin and erythromycin, at different doses on the extent and severity of ulcerative colitis caused by intracolonic administration of 3% aceticacid in rats. The lesions and the inflammatory response were assessed by histology and measurement of myeloperoxidase (MPO) activity, nitric oxide synthetase (NOS) and tumor necrosis factor alpha (TNF{alpha}) in colonic tissues. Inflammation following aceticacid instillation was characterized by oedema, diffuse inflammatory cell infiltration and necrosis. Increase in MPO, NOS and TNF{alpha} was detected in the colonic tissues. Administration of either azithromycin or erythromycin at different dosage (10, 20 and 40 mg/kg orally, daily for 5 consecutive days) significantly (P < 0.05) reduced the colonic damage, MPO and NOS activities as well as TNF{alpha} level. This reduction was highly significant with azithromycin when given at a dose of 40 mg/kg. It is concluded that azithromycin and erythromycin may have a beneficial therapeutic role in ulcerative colitis.

Mass spectra provide definitive identification of indole-3-aceticacid and abscisic acid in shoots of Coleus blumei, a species used for studying the hormone control of plant development since the early 1930s.

In the structure of the title compound, C(6)H(13)N(2)O(+)·C(2)H(3)O(2) (-)·H(2)O, the amide H atoms of the cations form centrosymmetric cyclic hydrogen-bonding associations incorporating two water mol-ecules [graph set R(4) (2)(8)], which are conjoint with cyclic water-bridged amide-amide associations [R(4) (4)(12)] and larger R(4) (4)(20) associations involving the water mol-ecule and the acetate anions, which bridge through the piperidinium H-bond donors, giving an overall three-dimensional framework structure. PMID:21589458

In the structure of the title compound, C6H13N2O+·C2H3O2 ?·H2O, the amide H atoms of the cations form centrosymmetric cyclic hydrogen-bonding associations incorporating two water mol­ecules [graph set R 4 2(8)], which are conjoint with cyclic water-bridged amide–amide associations [R 4 4(12)] and larger R 4 4(20) associations involving the water mol­ecule and the acetate anions, which bridge through the piperidinium H-bond donors, giving an overall three-dimensional framework structure. PMID:21589458

A simple procedure that uses a cellulose-enriched culture started from sewage sludge was developed for producing cellulolytic enzymes and converting cellulose to aceticacid rather than CH4 and CO2. In this procedure, the culture which converts cellulose to CH4 and CO2 was mixed with a synthetic medium and cellulose and heated to 80°C for 15 min before incubation. The end products formed were aceticacid, propionic acid, CO2, and traces of ethanol and H2. Supernatants from 6- to 10-day-old cultures contained 16 to 36 mM aceticacid. Cellulolytic enzymes in the supernatant were stable at 2°C under aerobic conditions for up to 4 weeks and had the ability to hydrolyze carboxymethyl cellulose, a microcystalline cellulose, cellobiose, xylan, and filter paper to reducing sugars. PMID:16345772

A stable yttria-stabilized zirconia (YSZ) sol has been synthesized by the controlled hydrolysis of zirconium n-butoxide. Aceticacid and nitric acid were used as chelating agent and catalyst, respectively. The addition of aceticacid and increasing the amount of nitric acids to the system significantly enhanced the sol stability. The viscosity of YSZ sol with the concentration less than 0.80

The production of auxins, such as indole-3-aceticacid (IAA), by rhizobacteria has been associated with plant growth promotion,\\u000a especially root initiation and elongation. Six indole-producing bacteria isolated from the rhizosphere of legumes grown in\\u000a Saskatchewan soils and identified as Pantoea agglomerans spp. were examined for their ability to promote the growth of canola, lentil and pea under gnotobiotic conditions and

Five species of social wasps were captured in trapping tests in Budapest (Hungary) that evaluated the attractiveness of aceticacid, isobutanol, 2-methyl-2-propanol, and heptyl butyrate. Both Vespula vulgaris (L.) and Vespula germanica (F.), were captured in traps baited with isobutanol, the combination of aceticacid and isobutanol, and the combination of aceticacid and 2-methyl-2- propanol. V. germanica did not

Saccharomyces cerevisiae and Neurospora crassa mutants defective in the so-called acetyl-CoA hydrolases Ach1p and Acu-8, respectively, display a severe growth defect on acetate, which is most strongly pronounced under acidic conditions. Acetyl-CoA hydrolysis is an energy wasting process and therefore denoted as a biochemical conundrum. Acetyl-CoA hydrolases show high sequence identity to the CoA-transferase CoaT from Aspergillus nidulans. Therefore, we extensively re-characterised the yeast enzyme. Ach1p showed highest specific activity for the CoASH transfer from succinyl-CoA to acetate and only a minor acetyl-CoA-hydrolase activity. Complementation of an ach1 mutant with the coaT gene reversed the growth defect on acetate confirming the in vivo function of Ach1p as a CoA-transferase. Our results imply that Ach1p is involved in mitochondrial acetate detoxification by a CoASH transfer from succinyl-CoA to acetate. Thereby, Ach1p does not perform the energy wasting hydrolysis of acetyl-CoA but conserves energy by the detoxification of mitochondrial acetate. PMID:19298859

Endogenous indoleacetic acid (IAA) levels of Euphorbia esula L. primary root and root buds were examined at three phenologic stages. High performance liquid chromatography coupled with fluorescence detection and gas chromatography-mass spectrometry, using (13)C(6)[benzene ring]-indole-3-aceticacid as internal standard, were used to measure root bud free and bound IAA levels in vegetative, full flower, and post-flower plants. Highest levels of free IAA (103 nanograms per gram fresh weight) were found in root buds during full flower. Esterified and amide IAA increased significantly in root buds of full flower and post-flower plants, but were not detectable in root buds of vegetative plants. Primary rootfree IAA was highest in vegetative and full flower plants (34.5 nanograms per gram fresh weight) and decreased by 50% in post-flower plants. PMID:16665432

To assess the potential of acetic and formic acid organosolv fractionation of wheat straw as basis of an integral biorefinery concept, detailed knowledge on yield, composition and purity of the obtained streams is needed. Therefore, the process was performed, all fractions extensively characterized and the mass balance studied. Cellulose pulp yield was 48% of straw dry matter, while it was 21% and 27% for the lignin and hemicellulose-rich fractions. Composition analysis showed that 67% of wheat straw xylan and 96% of lignin were solubilized during the process, resulting in cellulose pulp of 63% purity, containing 93% of wheat straw cellulose. The isolated lignin fraction contained 84% of initial lignin and had a purity of 78%. A good part of wheat straw xylan (58%) ended up in the hemicellulose-rich fraction, half of it as monomeric xylose, together with proteins (44%), minerals (69%) and noticeable amounts of acids used during processing. PMID:24508905

The liquid structure of pyridine-aceticacid mixtures have been investigated using neutron scattering at various mole fractions of aceticacid, ?HOAc = 0.33, 0.50, and 0.67 and compared to the structures of neat pyridine and aceticacid. Data has been modelled using empirical potential structure refinement (EPSR) with a 'free proton' reference model, which has no prejudicial weighting towards either the existence of molecular or ionised species. Analysis of the neutron scattering results shows the existence of hydrogen-bonded aceticacid chains with pyridine inclusions, rather than the formation of an ionic liquid by proton transfer. PMID:25670622

Either 5-[3H]indole-3-aceticacid (IAA) or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm of kernels of dark-grown Zea mays seedlings. The distribution of total radioactivity, radiolabeled indole-3-aceticacid, and radiolabeled ester conjugated indole-3-aceticacid, in the shoots was then determined. Differences were found in the distribution and chemical form of the radiolabeled indole-3-aceticacid in the shoot depending upon whether 5-[3H]indole-3-aceticacid or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm. We demonstrated that indole-3-acetyl-myo-inositol applied to the endosperm provides both free and ester conjugated indole-3-aceticacid to the mesocotyl and coleoptile. Free indole-3-aceticacid applied to the endosperm supplies some of the indole-3-aceticacid in the mesocotyl but essentially no indole-3-aceticacid to the coleoptile or primary leaves. It is concluded that free IAA from the endosperm is not a source of IAA for the coleoptile. Neither radioactive indole-3-acetyl-myo-inositol nor IAA accumulates in the tip of the coleoptile or the mesocotyl node and thus these studies do not explain how the coleoptile tip controls the amount of IAA in the shoot.

An acid labile branched PDMAEMA/acetal copolymer with amino group was synthesized by the DE-ATRP and followed by Michael addition. The degradation of the polymer was strongly pH-dependent. High nucleic acid transfection efficiency with low cytotoxicity was observed compared to its non-degradable copolymer counterpart. PMID:25358033

Recently, in our laboratories, samples of Murchison aceticacid were decarboxylated successfully and the carbon isotopic composition was measured for the methane released by this procedure. These analyses showed significant differences in C-13/C-12 ratios for the methyl and carboxyl carbons of the aceticacid molecule, strongly suggesting that more than one carbon source may be involved in the synthesis of the Murchison organic compounds. On the basis of this finding, laboratory model systems simulating cosmochemical synthesis are being studied, especially those processes capable of involving two or more starting carbon sources.

Separation of aceticacid/water mixtures by pervaporation was attempted over a range of compositions using polydimethylsiloxane (PDMS), aromatic polyamide (PA), and laminated polydimethylsiloxane-aromatic polyamide membranes. PDMS membranes are hydrophobic and aceticacid selective, whereas PA membranes are hydrophilic and water selective. When PDMS and PA membranes were laminated, with PDMS on the top side and in contact with the feed, water selectivity of the bottom PA membrane was intensified. On the other hand, when the PA membrane was on the top side and in contact with the feed, the selectivity was lowered. 10 refs., 4 figs.

A two-stage process consisting of anaerobic fermentation followed by sub-critical wet oxidation was used to generate aceticacid from sewage sludge at pilot scale. Volatile fatty acids, dominated by propionic acid, were produced over 4-6 days in the 2,000 L fermentation reactor, which also achieved 31% solids reduction. Approximately 96% of the carbon was retained in solution over the fermentation stage. Using a 200 L wet oxidation reactor operating in batch mode, the second stage achieved 98% volatile suspended solids (VSS) destruction and 67% total chemical oxygen demand (tCOD) destruction. Aceticacid produced in this stage was recalcitrant to further degradation and was retained in solution. The gross yield from VSS was 16% for aceticacid and 21% for volatile fatty acids across the process, higher than reported yields for wet oxidation alone. The pilot plant results showed that 72% of the incoming phosphorus was retained in the solids, 94% of the nitrogen became concentrated in solution and 41% of the carbon was converted to a soluble state, in a more degradable form. Aceticacid produced from the process has the potential to be used to offset ethanol requirements in biological nutrient removal plants. PMID:25768220

The activities of CeO2, Mn2O3-CeO2 and ZrO2-CeO2 were measured for aceticacid ketonization under reaction conditions relevant to pyrolysis vapor upgrading. We show that the catalyst ranking changed depending on the reaction conditions. Mn2O3-CeO2 was the most active catalyst at 350 oC, while ZrO2 - CeO2 was the most active catalyst at 450 oC. Under high CO2 and steam concentration in the reactants, Mn2O3-CeO2 was the most active catalyst at 350 and 450 °C. The binding energies of steam and CO2 with the active phase were calculated to provide the insight into the tolerance of Mn2O3-CeO2 to steam and CO2.

Aceticacid bacteria (AAB) live in sugar rich environments, including food matrices, plant tissues, and the gut of sugar-feeding insects. By comparing the newly sequenced genomes of Asaia platycodi and Saccharibacter sp., symbionts of Anopheles stephensi and Apis mellifera, respectively, with those of 14 other AAB, we provide a genomic view of the evolutionary pattern of this bacterial group and clues on traits that explain the success of AAB as insect symbionts. A specific pre-adaptive trait, cytochrome bo3 ubiquinol oxidase, appears ancestral in AAB and shows a phylogeny that is congruent with that of the genomes. The functional properties of this terminal oxidase might have allowed AAB to adapt to the diverse oxygen levels of arthropod guts. PMID:24682158

Indole-3-aceticacid (IAA) is produced from tryptophan through five synthesis pathways. A comprehensive method for the quantification of IAA and biosynthesis-related intermediates in a culture medium was developed. Sample preparation was simple with protein precipitation. The analytes were separated on a superficially porous C18 silica column and detected by electrospray ionization-tandem mass spectrometry in the positive ion multiple reaction monitoring mode. The limit of detection was 0.05 ?M, and the lower limits of quantification ranged from 0.05 to 2 ?M. The intra-day and inter-day precision and accuracy were less than 13.96%. Ion suppression was observed, and the deuterated internal standards were used to compensate for the matrix effect. The method was applied to analyze changes in tryptophan catabolism in a culture medium of Pseudomonas putida. The proposed method is robust and suitable for the systematic profiling of IAA biosynthesis in culture supernatant. PMID:25746752

Aceticacid bacteria (AAB) live in sugar rich environments, including food matrices, plant tissues, and the gut of sugar-feeding insects. By comparing the newly sequenced genomes of Asaia platycodi and Saccharibacter sp., symbionts of Anopheles stephensi and Apis mellifera, respectively, with those of 14 other AAB, we provide a genomic view of the evolutionary pattern of this bacterial group and clues on traits that explain the success of AAB as insect symbionts. A specific pre-adaptive trait, cytochrome bo3 ubiquinol oxidase, appears ancestral in AAB and shows a phylogeny that is congruent with that of the genomes. The functional properties of this terminal oxidase might have allowed AAB to adapt to the diverse oxygen levels of arthropod guts. PMID:24682158

Background: Contusions are common injuries that occur in athletics. If repeated, complications like myositis ossificans can occur. This case describes the examination and treatment of an athlete with an acute soft tissue injury. Objective: To describe the treatment approach used with a hockey player who sustained a soft tissue injury in his upper extremity. Case Description: A 19 year old male sustained a soft tissue injury to his upper arm while playing hockey. The athlete complained of pain rated a 2-3 out of 10. He had a well circumscribed, firm, 8 by 5 centimeter palpable mass present along the lateral arm, and was able to passively flex his elbow from 56° to 135°, demonstrating a 56° loss of elbow extension. Functionally, he was able to perform most activities of daily living, but he was unable to play hockey. Over 29 days, the athlete was treated one time with pulsed ultrasound and ice and nine times with iontophoresis using a 2% aceticacid solution. Additionally, the athlete performed pain-free active range of motion exercises for the elbow. Outcome: Following treatment, the athlete's pain resolved, the palpable mass disappeared, and his passive range of motion at the elbow was 0° to 135°. Most importantly, the athlete was able to resume playing hockey. Discussion: Aceticacid iontophoresis may be a successful intervention for soft tissue injuries of the upper extremity. In this case, it appeared helpful in decreasing the athlete's impairments and contributed to quicker resumption of all functional activities in less time than previously reported in the literature using traditional treatment interventions. PMID:21655380

Auxins are important for plant growth and development, including the control of fruit ripening. Conjugation to amino acids by indole-3-aceticacid (IAA)-amido synthetases is an important part of auxin homeostasis. The structure of the auxin-conjugating Gretchen Hagen3-1 (GH3-1) enzyme from grapevine (Vitis vinifera), in complex with an inhibitor (adenosine-5'-[2-(1H-indol-3-yl)ethyl]phosphate), is presented. Comparison with a previously published benzoate-conjugating enzyme from Arabidopsis thaliana indicates that grapevine GH3-1 has a highly similar domain structure and also undergoes a large conformational change during catalysis. Mutational analyses and structural comparisons with other proteins have identified residues likely to be involved in acyl group, amino acid, and ATP substrate binding. Vv GH3-1 is a monomer in solution and requires magnesium ions solely for the adenlyation reaction. Modeling of IAA and two synthetic auxins, benzothiazole-2-oxyacetic acid (BTOA) and 1-naphthaleneacetic acid (NAA), into the active site indicates that NAA and BTOA are likely to be poor substrates for this enzyme, confirming previous enzyme kinetic studies. This suggests a reason for the increased effectiveness of NAA and BTOA as auxins in planta and provides a tool for designing new and effective auxins. PMID:23136372

A methanogenic acetate enrichment was initiated by inoculation of an acetate-mineral salts medium with domestic anaerobic digestor sludge and maintained by weekly transfer for 2 years. The enrichment culture contained a Methanosarcina and several obligately anaerobic nonmethanogenic bacteria. These latter organisms formed varying degrees of association with the Methanosarcina, ranging from the nutritionally fastidious gram-negative rod called the satellite bacterium to the nutritionally nonfastidious Eubacterium limosum. The satellite bacterium had growth requirements for amino acids, a peptide, a purine base, vitamin B12, and other B vitamins. Glucose, mannitol, starch, pyruvate, cysteine, lysine, leucine, isoleucine, arginine, and asparagine stimulated growth and hydrogen production. Acetate was neither incorporated nor metabolized by the satellite organism. Since acetate was the sole organic carbon source in the enrichment culture, organism(s) which metabolize acetate (such as the Methanosarcina) must produce substrates and growth factors for associated organisms which do not metabolize acetate. PMID:677881

This study aimed to produce aceticacid from vegetable wastes by a new hydrothermal two-step process. A continuous flow reaction system with a maximum treatment capacity of 2 kg/h of dry biomass developed by us was used. Five kinds of vegetables of carrots, white radish, chinese cabbage, cabbage and potato were selected as the representation of vegetable wastes. First, batch experiments with the selected vegetables were performed under the condition of 300°C, 1 min for the first step, and 300°C, 1 min and 70% oxygen supply for the second step, which is the optimum condition for producing aceticacid in the case of using starch as test material. The highest yields of aceticacid from five vegetables were almost the same as those obtained from starch. Subsequently, similar the highest yield of aceticacid and experimental conditions from vegetables were also obtained successfully using the continuous flow reaction system. These results should be useful for developing an industrial scale process.

A series of 2-aryl(pyrrolidin-4-yl)aceticacids were synthesized and their biological activities were evaluated as agonists of S1P receptors. These analogs were able to induce lowering of lymphocyte counts in the peripheral blood of mice and were found to have good overall pharmacokinetic properties in rat.

Aluminium tubes with single and double coat solvent based and water based lacquers, based on epoxy-phenolic resins, were analysed. To determine the electrochemical parameters to correlate with the actual behaviour of a collapsible tube, impedance spectroscopy was used. The measurements were performed in 3% (v\\/v) aceticacid, at room temperature. After impedance measurements specimens surface were analysed by scanning electron

A simple, fast, and direct procedure was developed for the simultaneous determination of the methanol and aceticacid present as esters in the plant cell wall polysaccharide pectin. After base-hydrolysis of esters and acidification of pectin samples, headspace solid-phase microextraction was perfor...

The development of suitable biomimetic scaffolds is a fundamental requirement of tissue engineering. Although electrospinning has emerged as an effective method for producing such scaffolds of nanometer-sized fibers, the influence of solution characteristics on the morphology of the resulting nanofibers depends on each polymer solution system. In this study, gelatin nanofibers and microfibers were prepared via electrospinning using mixtures of water and aceticacid at different ratios as solvents. The viscosities of gelatin solutions before electrospinning were analyzed and two different behaviors were found as a function of the solvent composition, taking into account classic models of polymer science. A power law relationship between viscosity and gelatin concentration was found for each solvent system, and an empirical model including the influence of aceticacid was obtained for aqueous systems. Moreover, a ternary diagram considering gelatin, water, and aceticacid mass fractions was constructed as a tool to establish the electrospinnability domains in terms of fiber occurrence and morphology. Also, the isodiametric curves were defined in the fibers region. Finally, in order to correlate the diameter of electrospun nanofibers and the electrospinnability zones, the Berry number was used. However, as its only allows the range of electrospinnability to be established for a fixed solvent composition, a new dimensionless parameter (Bemod) was suggested to take into account all the aceticacid aqueous solutions as a single solvent. PMID:24870557

American pondweed (Potamogeton nodosus Poir.) is commonly found in northern California irrigation canals. The purpose of this study was to test the hypothesis that exposure of American pondweed winter buds to dilute aceticacid under field conditions would result in reduced survivorship and subsequ...

Bile leak after laparoscopic cholecystectomy is not uncommon, and it mainly occurs from the cystic duct stump and can be easily treated by endoscopic techniques. However, treatment for leakage from an isolated bile duct can be troublesome. We report a successful case of aceticacid sclerotherapy for bile leak from an isolated bile duct after laparoscopic cholecystectomy.

Lignocellulosic biomass is a potential substrate for ethanol production. However, pretreatment of lignocellulosic materials produces inhibitory compounds such as aceticacid, which negatively affect ethanol production by Saccharomyces cerevisiae. Supplementation of the medium with three metal ions (Zn(2+) , Mg(2+) , and Ca(2+) ) increased the tolerance of S. cerevisiae toward aceticacid compared to the absence of the ions. Ethanol production from xylose was most improved (by 34%) when the medium was supplemented with 2 mM Ca(2+) , followed by supplementation with 3.5 mM Mg(2+) (29% improvement), and 180 ?M Zn(2+) (26% improvement). Higher ethanol production was linked to high cell viability in the presence of metal ions. Comparative transcriptomics between the supplemented cultures and the control suggested that improved cell viability resulted from the induction of genes controlling the cell wall and membrane. Only one gene, FIT2, was found to be up-regulated in common between the three metal ions. Also up-regulation of HXT1 and TKL1 might enhance xylose consumption in the presence of aceticacid. Thus, the addition of ionic nutrients is a simple and cost-effective method to improve the aceticacid tolerance of S. cerevisiae. PMID:24924214

Immature zygotic embryos of sunflower (Helianthus annuus L.) produce somatic embryos when cultured on medium supplemented with a cytokinin as the sole source of exogenous growth regulators. The timing of the induction phase and subsequent morphogenic events have been well characterized in previous work. We address here the question of the role of endogenous indole-3-aceticacid (IAA), since auxins are

Use of a gas chromatograph equipped with a fused silica capillary column and a nitrogen-phosphorus detector permits selective detection of indole-3-aceticacid and other indoles at the low picogram level. The applicability of the method is demonstrated by the analysis of endogenous indole-3-aceticacid from shoots of Salix pentandra L.

In the radiolysis of aqueous solutions of indole, indole-3-aceticacid, indole-3-propionic acid, 1-naphthylacetic acid and phenylacetic acid, the absolute rate constants of their reactions with H and OH have been determined by competition kinetics using 2-propanol as the competitor. Hydrated electron reaction rate constants have been determined for indoie, indole-3-aceticacid and indole-3-propionic acid at pH = 11 using the

Herein, we report the influence of different combinations of initial concentration of aceticacid and ethanol on the removal of aceticacid from acidic wines by two commercial Saccharomyces cerevisiae strains S26 and S29. Both strains reduced the volatile acidity of an acidic wine (1.0 gl(-1) aceticacid and 11% (v/v) ethanol) by 78% and 48%, respectively. Aceticacid removal by strains S26 and S29 was associated with a decrease in ethanol concentration of 0.7 and 1.2% (v/v), respectively. Strain S26 revealed better removal efficiency due to its higher tolerance to stress factors imposed by acidic wines. Sulfur dioxide (SO(2)) in the concentration range 95-170 mg l(-1)inhibits the ability of both strains to reduce the volatile acidity of the acidic wine used under our experimental conditions. Therefore, deacidification should be carried out either in wines stabilized by filtration or in wines with SO(2)concentrations up to 70 mg l(-1). Deacidification of wines with the better performing strain S26 was associated with changes in the concentration of volatile compounds. The most pronounced increase was observed for isoamyl acetate (banana) and ethyl hexanoate (apple, pineapple), with an 18- and 25-fold increment, respectively, to values above the detection threshold. The acetaldehyde concentration of the deacidified wine was 2.3 times higher, and may have a detrimental effect on the wine aroma. Moreover, deacidification led to increased fatty acids concentration, but still within the range of values described for spontaneous fermentations, and with apparently no negative impact on the organoleptical properties. PMID:20390413

The environmental risk of chelating agents such as EDTA application to the heavy metals polluted soils and the stress on plant roots due to the abrupt increase metals concentration limit the wide commercial use of chelate-induced phytoextraction. Chelating agent ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) and auxin indole-3-aceticacid (IAA) were used for enhancing heavy metals uptake from soils by Zea mays L. (corn) in pot experiments. The metals content in plant tissues was quantified using an inductively coupled plasma mass spectrometer (ICP-MS). The results showed that the combination of IAA and EDTA increased the biomass by about 40.0% and the contents of Cu, Zn, Cd and Pb in corn shoots by 27.0%, 26.8%, 27.5% and 32.8% respectively, as compared to those in EDTA treatment. While NTA&IAA treatment increased the biomass by about 29.9% and the contents of Cu, Zn, Cd and Pb in corn shoots by 31.8%, 27.6%, 17.0% and 26.9% respectively, as compared to those in NTA treatment. These results indicated that corn growth was promoted, and the biomass and the accumulation of heavy metals in plant shoots were increased significantly with the addition of IAA, which probably helps to change the cell membrane properties and the biomass distribution, resulting in the alleviation of the phytotoxicity of metals and the chelating agents. PMID:17990562

A simple, rapid, sensitive and selective method for simultaneously determining 2-naphthoxyacetic acid (BNOA) and Indole-3-AceticAcid (IAA) in mixtures has been developed using derivation synchronous fluorescence spectroscopy based on their synchronous fluorescence. The synchronous fluorescence spectra were obtained with ?? = 100 nm in a pH 8.5 NaH2PO4-NaOH buffer solution, and the detected wavelengths of quantitative analysis were set at 239 nm for BNOA and 293 nm for IAA respectively. The over lapped fluorescence spectra were well separated by the synchronous derivative method. Under optimized conditions, the limits of detection (LOD) were 0.003 ?g/mL for BNOA and 0.012 ?g/mL for IAA. This method is simple and expeditious, and it has been successfully applied to the determination of 2-naphthoxyacetic acid and indole-3-aceticacid in fruit juice samples with satisfactory results. The samples were only filtrated through a 0.45 ?m membrane filter, which was free from the tedious separation procedures. The obtaining recoveries were in the range of 83.88-87.43% for BNOA and 80.76-86.68% for IAA, and the relative standard deviations were all less than 5.0%. Statistical comparison of the results with high performance liquid chromatography Mass Spectrometry (HPLC-MS) method revealed good agreement and proved that there were no significant difference in the accuracy and precision between these two methods.

A toxicologic and dermatologic review of 4-methylbenzyl acetate when used as a fragrance ingredient is presented. 4-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 4-methylbenzyl acetate were evaluated, then summarized, and includes: physical properties, skin irritation, skin sensitization, and elicitation data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22414643

Purpose. To evaluate the efficacy and long-term results of single-session 50% aceticacid sclerotherapy for the treatment of simple renal cysts, and to compare the therapeutic results of 5 and 20 min sclerosant dwell techniques. Methods. During the past 9 years, 50% aceticacid sclerotherapy was performed on 67 cysts in 66 patients. An aceticacid volume corresponding to a mean of 23% of the aspirated cyst volume was injected into the cysts. A 20 min dwell time with position changes was performed in 32 cysts (31 patients; group I) and 8% of volume for a 5 min dwell time in 35 cysts (35 patients; group II). Three- and 6-month sonographic or CT follow-up was performed for a minimum of 1 year. Complete regression was defined as no remaining cyst measurable on sonography with or without a scar at the renal cortex. Partial regression was defined as a decreased cyst volume compared with that before sclerotherapy. The Mann-Whitney U-test was used to compare the therapeutic results between the two groups. Results. For 67 simple renal cysts, complete regression on follow-up was observed in 21 of 32 cysts (66%; group I) and 22 of 35 cysts (63%; group II); the remaining 24 cysts all showed partial regression. The partial reduction rate of the cyst's volume was 97.4% (91.3-99.4%) in group I and 96.9% (90.8-99.5 %) in group II. There were no procedure-related major complications, and no statistically significant differences in the complete regression and partial volume reduction rates between the two groups (p > 0.05). Conclusion. Fifty percent aceticacid is an effective and safe sclerosing agent for simple renal cysts. Fifty percent aceticacid sclerotherapy with a 5 min sclerosant dwell time, using a volume of about 10% of the aspirated volume, is sufficient for satisfactory results of simple renal cyst sclerotherapy.

Ulipristal acetate is a progesterone receptor modulator. As an emergency contraceptive, a 30-mg micronized formulation is effective for use up to 120 h from unprotected sexual intercourse. Ulipristal acetate acts as an antagonist of the progesterone receptor at the transcriptional level and a competitive antagonist of glucocorticoid receptor function. In contrast to other contraceptives, it has little effect on sex hormone-binding globulin. Although a single small study demonstrated some potential endometrial effects after ulipristal acetate administration, the clinical relevance of these findings is unclear. The incidence of adverse events in clinical trials for emergency contraception has typically been minimal, with one study showing a higher than expected incidence of nausea upon ulipristal acetate use. Ulipristal acetate, like other emergency contraceptive products, can lengthen the time to the next expected menstruation. Ulipristal acetate may have several advantages over currently approved emergency contraceptives. When compared to levonorgestrel, ulipristal acetate maintains its efficacy for a full 120 h, whereas levonorgestrel formulations have declining efficacy over that time frame. Moreover, although the copper intrauterine device (IUD) is highly effective as an emergency contraceptive, accessibility is an issue since the IUD requires a skilled provider for insertion. PMID:20967297

Ulipristal acetate is the first selective progesterone receptor modulator approved for postcoital contraception in the US. It appears to be significantly more effective in inhibition of ovulation than other forms of emergency contraception. However, ulipristal acetate is structurally similar to mifepristone, and several lines of evidence suggest that a postfertilization mechanism of action is also operative. This mechanism of action is considered to be contragestive versus contraceptive. Ulipristal acetate administration is contraindicated in a known or suspected pregnancy; however, it could quite possibly be used as an effective abortifacient. Health-care providers should inform patients of the possibility of both mechanisms of action with use of this drug. PMID:21666088

Sodium acetate is known for its ability to supercool. It freezes at 130 degrees, but can exist as a liquid at a much lower temperature. In order to melt solidified sodium acetate, however, every single crystal must liquify, otherwise the material will recrystallize. Sodium acetate has been used as a deicer for roads and runways. It is also used a component of buffer systems and in the manufacture of pharmaceuticals and heat pads. The compound is quite stable. It may act as an irritant and be harmful if inhaled or absorbed through the skin.

Photochemistry and Photobiology. 1996. 63(5): Optically Pumped Chemiluminescence of Indole-3-Acetic January 1996 ABSTRACT the main ~ource of al. (4) have ~hown Optically pumped chemiluminescence of indole-3-sen- sitized photooxidation of luminal is a prospective technique for the creation of a new chemiluminescent

The vinegar pei harbors complex bacterial communities. Prior studies revealing the bacterial diversity involved were mainly conducted by culture-dependent methods and PCR-DGGE. In this study, 454 pyrosequencing was used to investigate the bacterial communities in vinegar pei during the aceticacid fermentation (AAF) of Tianjin Duliu aged vinegar (TDAV). The results showed that there were 7 phyla and 24 families existing in the vinegar pei, with 2 phyla (Firmicutes, Protebacteria) and 4 families (Lactobacillaceae, Acetobacteracae, Enterobacteriaceae, Chloroplast) predominating. The genus-level identification revealed that 9 genera were the relatively stable, consistent components in different stages of AAF, including the most abundant genus Lactobacillus followed by Acetobacter and Serratia. Additionally, the bacterial community in the early fermentation stage was more complex than those in the later stages, indicating that the accumulation of organic acids provided an appropriate environment to filter unwanted bacteria and to accelerate the growth of required ones. This study provided basic information of bacterial patterns in vinegar pei and relevant changes during AAF of TDAV, and could be used as references in the following study on the implementation of starter culture as well as the improvement of AAF process. PMID:25903266

The internal pH of Saccharomyces cerevisiae IGC 3507 III (a respiratory-deficient mutant) was measured by the distribution of [14C]propionic acid, when the yeast was fermenting glucose at pH 3.5, 4.5 and 5.5 in the presence of several concentrations of aceticacid and ethanol. Good correlation was obtained between fermentation rates and internal pH. For all external pH values tested, the

An acetate enrichment culture was initiated by inoculating anaerobic sludge from a mesophilic methane digestor into a mineral salts medium with calcium acetate as the sole carbon and energy source. This enrichment was maintained indefinitely by weekly transfer into medium of the same composition. A study of this enrichment disclosed an unexpected age-dependent inhibition of methanogenesis by H2 and formate which apparently differed from the inhibition by chloroform and benzyl viologen. This age-dependent inhibition indicated that microbial interactions of the mixed enrichment population may play a regulatory role in methane formation. Futhermore, stimulation of methanogenesis in the acetate enrichment by addition of yeast extract showed a nutrient limitation which indicated that syntrophic interactions leading to formation of growth factors may also occur. A model is presented to illustrate the possible interrelationships between methanogenic and nonmethanogenic bacteria in their growth and formation of methane and carbon dioxide from acetate. PMID:697356

For most liquids, the static relative dielectric permittivity is a decreasing function of temperature, because enhanced thermal motion reduces the ability of the molecular dipoles to orient under the effect of an external electric field. Monocarboxylic fatty acids ranging from acetic to octanoic acid represent an exception to this general rule. Close to room temperature, their dielectric permittivity increases slightly with increasing temperature. Herein, the causes for this anomaly are investigated based on molecular dynamics simulations of acetic and propionic acids at different temperatures in the interval 283-363 K, using the GROMOS 53A6(OXY) force field. The corresponding methyl esters are also considered for comparison. The dielectric permittivity is calculated using either the box-dipole fluctuation (BDF) or the external electric field (EEF) methods. The normal and anomalous temperature dependences of the permittivity for the esters and acids, respectively, are reproduced. Furthermore, in the EEF approach, the response of the acids to an applied field of increasing strength is found to present two successive linear regimes before reaching saturation. The low-field permittivity ?, comparable to that obtained using the BDF approach, increases with increasing temperature. The higher-field permittivity ?' is slightly larger, and decreases with increasing temperature. Further analyses of the simulations in terms of radial distribution functions, hydrogen-bonded structures, and diffusion properties suggest that increasing the temperature or the applied field strength both promote a relative population shift from cyclic (mainly dimeric) to extended (chain-like) hydrogen-bonded structures. The lower effective dipole moment associated with the former structures compared to the latter ones provides an explanation for the peculiar dielectric properties of the two acids compared to their methyl esters. PMID:22383366

Aceticacid bacteria (AAB) are broadly used in industrial food processing. Among them, members of the genera Asaia, Acetobacter, and Granulibacter were recently reported to be human opportunistic pathogens. We isolated AAB from clinical samples from three patients and describe here the clinical and bacteriological features of these cases. We report for the first time (i) the isolation of a Gluconobacter sp. from human clinical samples; (ii) the successive isolation of different AAB, i.e., an Asaia sp. and two unrelated Gluconobacter spp., from a cystic fibrosis patient; and (iii) persistent colonization of the respiratory tract by a Gluconobacter sp. in this patient. We reviewed the main clinical features associated with AAB isolation identified in the 10 documented reports currently available in the literature. Albeit rare, infections as well as colonization with AAB are increasingly reported in patients with underlying chronic diseases and/or indwelling devices. Clinicians as well as medical microbiologists should be aware of these unusual opportunistic pathogens, which are difficult to detect during standard medical microbiological investigations and which are multiresistant to antimicrobial agents. Molecular methods are required for identification of genera of AAB, but the results may remain inconclusive for identification to the species level. PMID:20826638

The identification of aceticacid bacteria (AAB) from sound grapes from the Canary Islands is reported in the present study. No direct recovery of bacteria was possible in the most commonly used medium, so microvinifications were performed on grapes from Tenerife, La Palma and Lanzarote islands. Up to 396 AAB were isolated from those microvinifications and identified by 16S rRNA gene sequencing and phylogenetic analysis. With this method, Acetobacter pasteurianus, Acetobacter tropicalis, Gluconobacter japonicus and Gluconacetobacter saccharivorans were identified. However, no discrimination between the closely related species Acetobacter malorum and Acetobacter cerevisiae was possible. As previously described, 16S-23S rRNA gene internal transcribed spacer (ITS) region phylogenetic analysis was required to classify isolates as one of those species. These two species were the most frequently occurring, accounting for more than 60% of the isolates. For typing the AAB isolates, both the Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR and (GTG)5-PCR techniques gave similar resolution. A total of 60 profiles were identified. Thirteen of these profiles were found in more than one vineyard, and only one profile was found on two different islands (Tenerife and La Palma). PMID:21903289

Plant-associated actinobacteria are rich sources of bioactive compounds including indole-derived molecules such as phytohormone indole-3-aceticacid (IAA). In view of few investigations concerning the biosynthesis of IAA by endophytic actinobacteria, this study evaluated the potential of IAA production in endophytic streptomycete isolates sourced from medicinal plant species Taxus chinensis and Artemisia annua. By HPLC analysis of IAA combined with molecular screening approach of iaaM, a genetic determinant of streptomycete IAA synthesis via indole-3-acetamide (IAM), our data showed the putative operation of IAM-mediated IAA biosynthesis in Streptomyces sp. En-1 endophytic to Taxus chinensis. Furthermore, using the co-cultivation system of model plant Arabidopsis thaliana and streptomycete, En-1 was found to be colonized intercellularly in the tissues of Arabidopsis, an alternative host, and the effects of endophytic En-1 inoculation on the model plant were also assayed. The phytostimulatory effects of En-1 inoculation suggest that IAA-producing Streptomyces sp. En-1 of endophytic origin could be a promising candidate for utilization in growth improvement of plants of economic and agricultural value. PMID:23512121

Ethylene induced an increase in the accumulation of 1-aminocyclopropane-1-carboxylate (ACC) oxidase transcript level and enzyme activity in the first internode of 5- to 6-day-old etiolated pea (Pisum sativum L.) seedlings. Indole-3-aceticacid (IAA), which stimulates ethylene production by enhancing ACC synthase activity, also caused an increase in ACC oxidase transcript and activity levels. The IAA-induced increase in ACC oxidase mRNA level and enzyme activity was blocked by 2,5-norbornadiene (NBD), a competitive inhibitor of ethylene action. This indicates that IAA induced ACC oxidase through the action of ethylene. The level of ACC synthase mRNA and enzyme activity started to increase less than 1 h after the start of IAA treatment, whereas ACC oxidase activity and transcript levels began to rise after 2 h of IAA treatment. These results indicate that the enzymes of ethylene biosynthesis are sequentially induced after treatment of intact pea seedlings with IAA. The increase in ACC synthase activity leads to the production of ACC, which is converted by the low constitutive level of ACC oxidase activity to ethylene. Through a positive feedback loop, ethylene promotes the accumulation of ACC oxidase mRNA and the increase in ACC oxidase activity. PMID:7599314

Electrospinning of chitosan solutions with poly(ethylene oxide) (PEO) in an aqueous solution of 2 wt% aceticacid was studied. The properties of the chitosan/PEO solutions, including conductivity, surface tension and viscosity, were measured. Morphology of the electrospun chitosan/PEO was observed by using scanning electron micrographs. Results showed that the ultrafine fibers could be generated after addition of PEO in 2:1 or 1:1 mass ratios of chitosan to PEO from 4-6 wt% chitosan/PEO solutions at 15 kV voltage, 20 cm capillary-collector distance and flow rate 0.1 ml/h. During electrospinning of the chitosan/PEO solutions, ultrafine fibers with diameters from 80 nm to 180 nm were obtained, while microfibers with visually thicker diameters could be formed as well. Results of X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and differential scanning calorimeter exhibited the larger electrospun microfibers were almost entirely made from PEO, while the electrospun ultrafine fibers mainly contained chitosan. PMID:15255527

Microalgae have tremendous potential as a renewable feedstock for the production of liquid transportation fuels. In natural waters, the importance of physical associations and biochemical interactions between microalgae and bacteria is generally well appreciated, but the significance of these interactions to algal biofuels production have not been investigated. Here, we provide a preliminary report on the frequency of co-occurrence between indole-3-aceticacid (IAA)-producing bacteria and green algae in natural and engineered ecosystems. Growth experiments with unicellular algae, Chlorella and Scenedesmus, revealed IAA concentration-dependent responses in chlorophyll content and dry weight. Importantly, discrete concentrations of IAA resulted in cell culture synchronization, suggesting that biochemical priming of cellular metabolism could vastly improve the reliability of high density cultivation. Bacterial interactions may have an important influence on algal growth and development; thus, the preservation or engineered construction of the algal-bacterial assembly could serve as a control point for achieving low input, reliable production of algal biofuels. PMID:24879600

Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-aceticacid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production, providing a new framework in which to explore endophyte-plant interactions. PMID:24086270

We have isolated from plant surfaces several bacteria with the ability to catabolize indole-3-aceticacid (IAA). One of them, isolate 1290, was able to utilize IAA as a sole source of carbon, nitrogen, and energy. The strain was identified by its 16S rRNA sequence as Pseudomonas putida. Activity of the enzyme catechol 1,2-dioxygenase was induced during growth on IAA, suggesting that catechol is an intermediate of the IAA catabolic pathway. This was in agreement with the observation that the oxygen uptake by IAA-grown P. putida 1290 cells was elevated in response to the addition of catechol. The inability of a catR mutant of P. putida 1290 to grow at the expense of IAA also suggests a central role for catechol as an intermediate in IAA metabolism. Besides being able to destroy IAA, strain 1290 was also capable of producing IAA in media supplemented with tryptophan. In root elongation assays, P. putida strain 1290 completely abolished the inhibitory effect of exogenous IAA on the elongation of radish roots. In fact, coinoculation of roots with P. putida 1290 and 1 mM concentration of IAA had a positive effect on root development. In coinoculation experiments on radish roots, strain 1290 was only partially able to alleviate the inhibitory effect of bacteria that in culture overproduce IAA. Our findings imply a biological role for strain 1290 as a sink or recycler of IAA in its association with plants and plant-associated bacteria. PMID:15870323

Intrarectal infusion of butyrate improves colorectal disorders including ulcerative colitis (UC). However, it is not established whether systemically administered butyrate benefits such patients. The current study aimed at exploring and comparing the potential of intraperitoneally, intrarectally, and orally administered butyrate against aceticacid (AA)-induced UC in rats. Intrarectal administration of 2 ml of 50% AA was done after or without prior treatment of rats for 7 consecutive days with 100 mg/kg sodium butyrate (SB) intraperitoneally, intrarectally, or orally. Rats were sacrificed after 48 h of AA-treatment. Subsequently, colon sections were processed routinely for histopathological examination. We clinically observed diarrhea, loose stools, and hemoccult-positive stools, and histologically, epithelial loss and ulceration, crypt damage, goblet cell depletion, hemorrhage, and mucosal infiltration of inflammatory cells. The changes were significantly reduced by intraperitoneal, intrarectal, or oral butyrate, with intraperitoneal butyrate exhibiting the highest potency. It is concluded that intraperitoneal administration of butyrate abrogates the lesions of AA-induced UC and its potency surpasses that of intrarectal or oral butyrate. PMID:25743124

Formic and aceticacids were measured in a scrub-grass savanna and in a nearby semideciduous forest. Gaseous HCOOH and CH3COOH were collected using the mist-scrubber technique, and were determined using ion chromatography. A strong diurnal cycle was observed at both sites, with higher mixing ratios during daytime. Concentrations in the savanna were always higher than in the forest. Most of the time HCOOH/CH3COOH ratios greater than one were recorded at the savanna site, and ratios less than one at the forest site. Boundary-layer mixing ratios in the savanna region, derived from measurements during midday, are 1.3 +/- 0.4 ppbv and 0.7 +/- 0.3 ppbv for HCOOH and dCH3COOH. Dry depositions velocities between 0.5 and 1 cm sq were estimated for the savanna region. Atmospheric residence times of less than 3 days and greater than 5 days were estimated for the rainy and dry season, respectively.

The adsorption of complex molecules at mineral surfaces are crucial ingredients for understanding the mechanisms that rule the interaction between minerals and the biosphere and for predicting both the stability and the reactivity of minerals. The present work focuses mainly on the early stages of different adsorption reactions occurring at both the cleavage surface and a high-index vicinal surface of galena (PbS). We have studied the dissociation mechanism of water and aceticacid on the galena surfaces by means of ab initio calculations within the framework of the density functional theory in the generalized gradient approximation and of pseudopotential approach. The calculated adsorption energies of the molecules indicate the stepped surface as the most reactive, as expected. The free energy surface during the reaction process has been explored via metadynamics[1]. The optimized configurations of both reactants and products obtained, were then used to accurately calculate the dissociation energy via the Nudge Elastic Band method[2]. [1] A. Laio and M. Parrinello, PNAS 99, 12562 (2002). [2] G. Mills and H. Jonsson, Phys. Rev. Lett. 72, 1124 (1994).

Recently, we reported that a combination of indole-3-aceticacid (IAA) and horseradish peroxidase (HRP) induces apoptosis in G361 human melanoma cells. However, the apoptotic mechanism involved has been poorly studied. It is known that when IAA is oxidized by HRP, free radicals are produced, and since oxidative stress can induce apoptosis, we investigated whether reactive oxygen species (ROS) are involved in IAA/HRP-induced apoptosis. Our results show that IAA/HRP-induced free radical production is inhibited by catalase, but not by superoxide dismutase or sodium formate. Furthermore, catalase was found to prevent IAA/HRP-induced apoptotic cell death, indicating that IAA/HRP-produced hydrogen peroxide (H2O2) may be involved in the apoptotic process. Moreover, the antiapoptotic effect of catalase is potentiated by NADPH, which is known to protect catalase. On further investigating the IAA/HRP-mediated apoptotic pathway, we found that the IAA/HRP reaction leads to caspase-3 activation and poly(ADP-ribose) polymerase (PARP) cleavage, which was also blocked by catalase. Additionally, we found that IAA/HRP produces H2O2 and induces peroxiredoxin (Prx) sulfonylation. Consequently, our results suggest that H2O2 plays a major role in IAA/HRP-induced apoptosis. PMID:16460736

Indole-3-aceticacid (IAA) activation by horseradish peroxidase (HRP) has been suggested as a new cancer therapy. Interestingly, we found that ultraviolet B UVB radiation also can activate IAA and produce free radicals in a dose-dependent manner. In this study, we attempted to identify the free radicals generated by UVB-irradiated IAA (IAAUVB), and to determine whether IAAUVB can induce the apoptosis of G361 human melanoma cells. Since IAA/HRP produces reactive oxygen species (ROS), we examined whether IAAUVB-generated radicals include ROS. Our results show that IAAUVB-induced free radical production is not inhibited by catalase, superoxide dismutase, or sodium formate, indicating that ROS are not generated by IAAUVB. On the other hand, IAAUVB caused lipid peroxidation, and this was blocked by Trolox, a water-soluble vitamin E derivative. Moreover, we found that IAAUVB caused apoptotic cell death and that this was inhibited by a low temperature. We further investigated IAAUVB-mediated apoptotic pathways, and found that IAAUVB causes caspase-8, Bid, caspase-3 activation, and poly (ADP-ribose) polymerase (PARP) cleavage. In addition, these apoptotic pathways were also blocked by low temperature. From these results, we propose that IAAUVB-induced free radicals cause human melanoma cell apoptosis via a death receptor-mediated apoptotic pathway. PMID:17142972

A liquid chromatography–tandem mass spectrometry (LC–MS\\/MS) method was developed for simultaneous determination of three representative phytohormones in plant samples: gibberellic acid (GA3), indole-3-aceticacid (IAA) and abscisic acid (ABA). A solid-phase extraction (SPE) pretreatment method was used to concentrate and purify the three phytohormones of different groups from plant samples. The separation was carried out on a C18 reversed-phase column,

A self-assembled supramolecular host catalyzes the hydrolysis of acetals in basic aqueous solution. The mechanism of hydrolysis is consistent with the Michaelis-Menten kinetic model. Further investigation of the rate limiting step of the reaction revealed a negative entropy of activation ({Delta}S{double_dagger} = -9 cal mol{sup -1}K{sup -1}) and an inverse solvent isotope effect (k(H{sub 2}O)/k(D{sub 2}O) = 0.62). These data suggest that the mechanism of hydrolysis that takes place inside the assembly proceeds through an A-2 mechanism, in contrast to the A-1 mechanism operating in the uncatalyzed reaction. Comparison of the rates of acetal hydrolysis in the assembly with the rate of the reaction of unencapsulated substrates reveals rate accelerations of up to 980 over the background reaction for the substrate diethoxymethane.

METHANOL extracts of immature seeds of Pisum sativum exhibited fairly strong auxin-like activity when assayed by hypocotyl swelling of Phaseolus mungo1. We isolated an active principle from the neutral fraction of immature seeds2; it was identified as methyl 4-chloroindolyl-3-acetate by synthesis. Preliminary examination showed that its auxin activity against Avena first internode and section tests was comparable with that of

A thermophilic (60/sup 0/C), anaerobic coculture conspired of an acetate-oxidizing eubacterial rod (AOR) and a H/sub 2/-using methanogen, Methanobacterium sp. strain THF, was studied. The AOR was isolated from the coculture by dilution into medium, with ethylene glycol. It grew on ethylene glycol, 1,2 propanediol, formate, pyruvate, glycinebetaine, and H/sub 2/-CO/sub 2/, usually forming acetate as the main product. Evidence was obtained consistent with the hypothesis that the AOR oxidized acetate via a series of reactions resembling the reversal of the acetyl CoA acetogenesis pathway. Two key enzymes were present in high activity; carbon monoxide dehydrogenase (CODH) and formate dehydrogenase (FDH), although formyltetrahydrofolate synthetase was not detectable. Tetrahydrofolate, an important C/sub 1/ carrier in acetogens, was not detectable indirectly via enzyme assays, inhibitor studies, or fluorescence spectra, suggesting an alternate carries in the AOR. Anaerobic activity stains for CODH in native polyacrylamide gels showed a novel major band in the coculture not detected in the component organisms, suggesting regulation of this enzyme and the reversal of the pathway. Enzyme assays also indicated regulate of CODH and FDH in Methanobacterium. THF.

A study was undertaken using the photoaffinity labeling agent, tritiated 5-azidoindole-3-aceticacid ([3H],5-N3IAA), to identify cells in the etiolated maize (Zea mays L.) shoot which transport auxin. Transport of [3H],5-N3IAA was shown to be polar, inhibited by 2,3,5-triiodobenzoic acid (TIBA) and essentially freely mobile. There was no detectable radiodecomposition of [3H],5-N3IAA within tissue kept in darkness for 4 hours. Shoot tissue which had taken up [3H],5-N3IAA was irradiated with ultraviolet light to covalently fix the photoaffinity labeling agent within cells that contained it at the time of photolysis. Subsequent microautoradiography showed that all cells contained radioactivity; however, the amount of radioactivity varied among different cell types. Epidermal cells contained the most radioactivity per area, approximately twofold more than other cells. Parenchyma cells in the mature stelar region contained the next largest amount and cortical cells, sieve tube cells, tracheary cells, and all cells in the leaf base contained the least amount of the radioactive label. Two observations suggest that the auxin within the epidermal cells is transported in a polar manner: (a) the amount of auxin in the epidermal cells is greatly reduced in the presence of TIBA, and (b) auxin accumulates on the apical side of a wound in the epidermis and is absent on the basal side. While these results indicate that auxin in the epidermis is polarly transported, this tissue cannot be the only pathway since the epidermis is only a small fraction of the shoot volume. The greater than twofold difference between the concentration of auxin in the epidermal and subtending cells demonstrates that physiological differences in the concentration of auxin can occur between adjacent cells. Images Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:16667572

In the search for pharmacological active new derivatives of 1,2-benzisothiazolin-3-on amides of (3-oxo-1,2-benzisothiazolin-2-yl)aceticacid and 3-(3-oxo-1,2-benzisothiazolin-2-yl)propionic acid were obtained. In the reaction of these amides with formaldehyde and various second aryl amines the title compounds are formed. Morpholinmethylamide of (3-oxo-1,2-benzisothiazolin-2-yl)aceticacid showed activity against Trichomonas vaginalis. In the reaction of ethyl esters of (3-oxo-1,2-benzisothiazolin-2-yl) acetic- and -propionic acids with hydrazine hydrate products of ring-opening of isothiazole-2,2'-dithio-bis [N- (ethoxycarbonylmethyl)benzamide] and 2,2'-dithio-bis[N-(ethoxycarbonylethyl)benzamide are formed. PMID:1811228

Indole-3-acetyl-myo-inositol esters have been demonstrated to be endogenous components of etiolated Zea mays shoots tissue. This was accomplished by comparison of the putative compounds with authentic, synthetic esters. The properties compared were liquid and gas-liquid chromatographic retention times and the 70-ev mass spectral fragmentation pattern of the pentaacetyl derivative. The amount of indole-3-acetyl-myo-inositol esters in the shoots was determined to be 74 nanomoles per kilogram fresh weight as measured by isotope dilution, accounting for 19% of the ester indole-3-aceticacid of the shoot. This work is the first characterization of an ester conjugate of indole-3-acetateacid from vegetative shoot tissue using multiple chromatographic properties and mass spectral identification. The kernel and the seedling shoot both contain indole-3-acetyl-myo-inositol esters, and these esters comprise approximately the same percentage of the total ester content of the kernel and of the shoot.

The heavy-metal content of aquatic plants is mainly dependent upon their ecological system. This study indicated that although the toxic heavy-metal contents could be above the recommended maximum levels depending upon their concentrations in growing water, they can be decontaminated by pickling with 5% aceticacid solution. Almost all Cd, Hg, Ba, or Sb and 99.5% Pb, 96.7% Ag, or 97.1% Al were removed from Water Spinach leaves by soaking in aceticacid solution. For Water-Shield leaves, almost all Cd, Hg, Pb, Ba, or Sb and 95.0% Ag or 96.1% Al were removed. For Watercress leaves, almost all Cd, Hg, Ba, or Sb and 99.0% Pb or 99.7% Ag were removed. For Water Hyacinth leaves, almost all Cd, Ba, or Sb and 99.0% Hg, 98.5% Pb, 95.0% Ag, or 98.7% Al were removed. PMID:21888602

The inability of fermenting microorganisms to use mixed carbon components derived from lignocellulosic biomass is a major technical barrier that hinders the development of economically viable cellulosic biofuel production. In this study, we integrated the fermentation pathways of both hexose and pentose sugars and an aceticacid reduction pathway into one Saccharomyces cerevisiae strain for the first time using synthetic biology and metabolic engineering approaches. The engineered strain coutilized cellobiose, xylose, and aceticacid to produce ethanol with a substantially higher yield and productivity than the control strains, and the results showed the unique synergistic effects of pathway coexpression. The mixed substrate coutilization strategy is important for making complete and efficient use of cellulosic carbon and will contribute to the development of consolidated bioprocessing for cellulosic biofuel. The study also presents an innovative metabolic engineering approach whereby multiple substrate consumption pathways can be integrated in a synergistic way for enhanced bioconversion. PMID:25587748

Certain Aspergillus and Penicillium strains isolated from soil grow well and degrade a commercial sample of polyvinyl acetate (PVA, 4.5 g liter-1) when it is used as the only carbon source. These strains showed an increase in dry weight after 11 days of incubation, along with a depletion of carbohydrates, protein, and deoxyribonucleic acid. This was interpreted as an active turnover of the above metabolites during the degradation. This effect was greatly enhanced by equilibrating the carbon:nitrogen ratio by addition of yeast extract in the original culture. The increase in esterase activity and the loss of viscosity were also considered evidence of the fungal degradation. Isolation of the enzyme was attempted, but unsuccessful. PMID:3181066

During hemodialysis, amino acids (AA) are lost in the ultrafiltrate with consequent modification of their plasma profile. The aim of this cross-sectional study was to evaluate intradialytic changes of plasma AA levels during a single session of hemodiafiltration with endogenous reinfusion (HFR) versus acetate-free biofiltration (AFB). 48 patients chronically treated with HFR or AFB were matched 1:1 for age, gender,

Pyrrolopiperidinone aceticacids (PPAs) were identified as highly potent CRTh2 receptor antagonists. In addition, many of these compounds displayed slow-dissociation kinetics from the receptor. Structure-kinetic relationship (SKR) studies allowed optimisation of the kinetics to give potent analogues with long receptor residence half-lives of up to 23 h. Low permeability was a general feature of this series, however oral bioavailability could be achieved through the use of ester prodrugs. PMID:25437503

The present article describes the adsorption behaviors of Cu2+ and Cd2+ on mercapto-aceticacid modified orange peel. The prepared adsorbents were characterized using Malvern Zetasizer, infrared spectrophotometer and infrared C–S analyzer. The effect of various parameters like solution pH, contact time, and initial metal ion concentration on adsorption efficiencies of these two metals were studied systematically by batch experiments. Adsorption

The performance of clear delta traps baited with 3.0 mg of pear ester, ethyl (E,Z)-2,4-decadienoate, and 5.0 ml of aceticacid in separate lures was compared with orange delta traps baited with a single lure containing 3.0 mg of both pear ester and the sex pheromone, (E,E)-8,10-dodecadien-1-ol (codlemone) for codling moth, Cydia pomonella (L.), in apple, Malus domestica (Borkhausen). Residual analyses and field tests demonstrated that both the pear ester and aceticacid lures were effective for at least 8 wk. The two trap-lure combinations caught a similar number of total moths in an orchard treated with sex pheromone dispensers during short-term trials in 2008. However, the mean catch of female moths was significantly higher and male moths significantly lower in clear traps baited with pear ester and aceticacid versus orange traps baited with pear ester and codlemone. Season-long studies were conducted with these two trap-lure combinations in orchards treated with (n = 6) and without (n = 7) sex pheromone dispensers during 2009. The two trap-lure combinations caught similar numbers of moths in dispenser-treated orchards. In contrast, total catch was significantly higher (>2-fold) in the orange compared with the clear traps in untreated orchards. The clear caught >6-fold more females than the orange trap in both types of orchards. These studies suggest that deploying clear delta traps baited with pear ester and aceticacid can be an effective monitoring tool for female codling moth and an alternative to codlemone-baited traps in sex pheromone-treated orchards. PMID:22127179

In present study, photoionization and dissociation of aceticacid dimers have been studied with the synchrotron vacuum ultraviolet photoionization mass spectrometry and theoretical calculations. Besides the intense signal corresponding to protonated cluster ions (CH{sub 3}COOH){sub n}{center_dot}H{sup +}, the feature related to the fragment ions (CH{sub 3}COOH)H{sup +}{center_dot}COO (105 amu) via {beta}-carbon-carbon bond cleavage is observed. By scanning photoionization efficiency spectra, appearance energies of the fragments (CH{sub 3}COOH){center_dot}H{sup +} and (CH{sub 3}COOH)H{sup +}{center_dot}COO are obtained. With the aid of theoretical calculations, seven fragmentation channels of aceticacid dimer cations were discussed, where five cation isomers of aceticacid dimer are involved. While four of them are found to generate the protonated species, only one of them can dissociate into a C-C bond cleavage product (CH{sub 3}COOH)H{sup +}{center_dot}COO. After surmounting the methyl hydrogen-transfer barrier 10.84 {+-} 0.05 eV, the opening of dissociative channel to produce ions (CH{sub 3}COOH){sup +} becomes the most competitive path. When photon energy increases to 12.4 eV, we also found dimer cations can be fragmented and generate new cations (CH{sub 3}COOH){center_dot}CH{sub 3}CO{sup +}. Kinetics, thermodynamics, and entropy factors for these competitive dissociation pathways are discussed. The present report provides a clear picture of the photoionization and dissociation processes of the aceticacid dimer in the range of the photon energy 9-15 eV.

A set of 25 coumarin-4-aceticacid benzylidene hydrazides were synthesized and characterized by NMR, IR and mass spectroscopic techniques. The compounds were evaluated for their anti-tubercular activity against Mycobacterium tuberculosis H37Rv strain using the BACTEC 460 system to determine percentage inhibition. To understand the relationship between structure and activity, a 3D-QSAR analysis has been carried out by Comparative Molecular Field

Time- and vehicle-related variability of bladder and urethral rhabdosphincter (URS) activity as well as cardiorespiratory and blood chemistry values were examined in the aceticacid-induced bladder irritation model in ?-chloralose-anesthetized female cats. Additionally, bladder and urethra were evaluated histologically using Mason trichrome and toluidine blue staining. Urodynamic, cardiovascular and respiratory parameters were collected during intravesical saline infusion followed by aceticacid (0.5%) to irritate the bladder. One hour after starting aceticacid infusion, a protocol consisting of a cystometrogram, continuous infusion-induced rhythmic voiding contractions, and a 5 min “quiet period” (bladder emptied without infusion) was precisely repeated every 30 minutes. Administration of vehicle (saline i.v.) occurred 15 minutes after starting each of the first 7 cystometrograms and duloxetine (1mg/kg i.v.) after the 8th. Aceticacid infusion into the bladder increased URS-EMG activity, bladder contraction frequency, and decreased contraction amplitude and capacity, compared to saline. Bladder activity and URS activity stabilized within 1 and 2 hours, respectively. Duloxetine administration significantly decreased bladder contraction frequency and increased URS-EMG activity to levels similar to previous reports. Cardiorespiratory parameters and blood gas levels remained consistent throughout the experiment. The epithelium of the bladder and urethra were greatly damaged and edema and infiltration of neutrophils in the lamina propria of urethra were observed. These data provide an ample evaluation of the health of the animals, stability of voiding function and appropriateness of the model for testing drugs designed to evaluate lower urinary tract as well as cardiovascular and respiratory systems function. PMID:24040064

Auxin regulates various aspects of plant growth and development. The AUXIN\\/INDOLE-3-ACETICACID (Aux\\/IAA) genes encode short-lived transcriptional repressors that are targeted by the TRANSPORT INHIBITOR RESPONSE1\\/AUXIN RECEPTOR F-BOX proteins. The Aux\\/IAA proteins regulate auxin-mediated gene expression by interacting with members of the AUXIN RESPONSE FACTOR protein family. Aux\\/IAA function is poorly understood; herein, we report the identification and characterization of

To investigate novel pathways involved in auxin biosynthesis, transport, metabolism, and response, we have developed a high-throughput screen for indole-3-aceticacid (IAA) levels. Historically, the quantitative analysis of IAA has been a cumbersome and time-consuming process that does not lend itself to the screening of large numbers of samples. The method described here can be performed with or without an

In order to suppress fast degradation of ZnS-type phosphors applied in field emission displays (FEDs), the surface coating and encapsulation are expected to be an effective way. The titania nanocoatings are obtained by a sol–gel route using tetrabutyl titanate (TBT) as the precursor in this paper. With the addition of the glacial aceticacid (HAc), due to the formation of

The combination of indole-3-aceticacid (IAA) and horseradish peroxidase (HRP) has recently been proposed as a novel cancer therapy. However, the mechanism underlying the cytotoxic effect involved is substantially unknown. Here, we show that IAA\\/HRP treatment induces apoptosis in G361 human melanoma cells, whereas IAA or HRP alone have no effect. It is known that IAA produces free radicals when

The presence of water in biofuels poses the question of how it affects the frictional performance of additives in fuels containing organic substances. To investigate the effect of water on the adsorption of molecules present in fuel and its additives we simulated within the framework of density functional theory the adsorption of ethanol, isooctane (2,2,4-trimethylpentane), and aceticacid on a bare and a water-covered Fe(100) surface. Van der Waals interactions are taken into account in our computations. In those molecules, where dispersion forces contribute significantly to the binding mechanism, the water layer has a stronger screening effect. Additionally, this effect can be enhanced by the presence of polar functional groups in the molecule. Thus, with the introduction of a water layer, the adsorption energy of isooctane and ethanol is reduced but it is increased in the case of the aceticacid. The adsorption configuration of ethanol is changed, while the one of aceticacid is moderately, and for isooctane only very slightly altered. Therefore, the effect of a water layer in the adsorption of organic molecules on an Fe(100) surface strongly depends on the type of bond and consequently, so do the tribological properties. PMID:25243045

The presence of water in biofuels poses the question of how it affects the frictional performance of additives in fuels containing organic substances. To investigate the effect of water on the adsorption of molecules present in fuel and its additives we simulated within the framework of density functional theory the adsorption of ethanol, isooctane (2,2,4-trimethylpentane), and aceticacid on a bare and a water-covered Fe(100) surface. Van der Waals interactions are taken into account in our computations. In those molecules, where dispersion forces contribute significantly to the binding mechanism, the water layer has a stronger screening effect. Additionally, this effect can be enhanced by the presence of polar functional groups in the molecule. Thus, with the introduction of a water layer, the adsorption energy of isooctane and ethanol is reduced but it is increased in the case of the aceticacid. The adsorption configuration of ethanol is changed, while the one of aceticacid is moderately, and for isooctane only very slightly altered. Therefore, the effect of a water layer in the adsorption of organic molecules on an Fe(100) surface strongly depends on the type of bond and consequently, so do the tribological properties. PMID:25243045

Fermentation of CO or syngas offers an attractive route to produce bioethanol. However, during the bioconversion, one of the challenges to overcome is to reduce the production of aceticacid in order to minimize recovery costs. Different experiments were done with Clostridium autoethanogenum. With the addition of 0.75?M tungsten, ethanol production from carbon monoxide increased by about 128% compared to the control, without such addition, in batch mode. In bioreactors with continuous carbon monoxide supply, the maximum biomass concentration reached at pH 6.0 was 109% higher than the maximum achieved at pH 4.75 but, interestingly, at pH 4.75, no aceticacid was produced and the ethanol titer reached a maximum of 867mg/L with minor amounts of 2,3-butanediol (46mg/L). At the higher pH studied (pH 6.0) in the continuous gas-fed bioreactor, almost equal amounts of ethanol and aceticacid were formed, reaching 907.72mg/L and 910.69mg/L respectively. PMID:25812815

We investigated the exchange of formic and aceticacids between the atmosphere and various tree species such as beech ( Fagus sylvatica L.), ash ( Fraxinus excelsior L.), spruce ( Picea abies L.) Karst, holm oak ( Quercus ilex L.), and birch ( Betula pendula L.). and some crop-plant species such as corn ( Zea mays, var. Banjo), pea ( Pisum sativum, var. Solara), barley ( Hordeum vulgare, var. Igri) and oat (Avena sativa, var. Wiesel). All experiments were done with dynamic enclosures flushed with purified oxidant-free air, containing only low or controlled amounts of the two acids. Significant and light-triggered emission of both acids from all tree species was observed. For one tree species (ash) a seasonal large increase in fall due to early leaf decomposition was found. The standard emission factors (30°C and PAR=1000 ?mol m 2 s -1) given as (nmol m -2 min -1) for acetic and formic acids, respectively, were 8.1 and 29.7 (ash, autumn), 1.0 and 3.3 (ash, summer), 0.9 and 1.4 (beech), 0.7 and 1.45 (spruce), 1.9 and 2.4 (Holm oak) and 1.7 and 6.7 (birch). Rough estimation of global annual emissions range between 20 and 130 Gmol formic acid and 10 and 33 Gmol aceticacid. These numbers reflect a 15-30% contribution by forest emissions to the continental organic acid budget. As compared to the global total NMHC emissions low molecular weight organic acids are of minor importance. In contrast to the trees, none of the crop-plant species investigated showed an emission, but always a clear deposition of both acids. Both emission from trees as well as uptake by the agricultural plants could be related to transpiration rates and leaf conductances.

Tributyrin (TBU) is a good dietary source of butyrate and has beneficial effects on the maintenance of normal intestinal morphology. The present study tested the hypothesis that dietary TBU supplementation could alleviate intestinal injury in the aceticacid (ACA)-induced porcine model of colitis. A total of eighteen piglets (25 d old) were randomly allocated to one of three treatment groups (control, ACA and TBU). The control and ACA groups were fed a basal diet and the TBU group was fed the basal diet supplemented with 0·1 % TBU. On day 15 of the trial, under anaesthesia, a soft catheter was inserted into the rectum of piglets (20-25 cm from the anus), followed by administration of either saline (control group) or ACA (10 ml of 10 % ACA solution for ACA and TBU groups). On day 22 of the trial, after venous blood samples were collected, piglets were killed to obtain mid-ileum and mid-colon mucosae. Compared with the control group, the ACA group exhibited an increase (P

The iac locus is involved in indole-3-aceticacid (IAA) catabolism in Acinetobacter baumannii. Nine structural genes of iac are transcribed in the same direction, whereas iacR, which encodes a MarR-type transcriptional regulator, is transcribed in the opposite direction. The IacA protein, which is encoded by the second structural gene of the iac locus, is expressed in an IAA-dependent manner. Here, we characterized gene expression from this locus in wild type A. baumannii and in an iacR mutant; this revealed that the iacH promoter is negatively regulated by IacR. The transcriptional site of iacH was determined by using 5' rapid amplification of cDNA ends; one IacR-binding site was identified between positions -35 and +28 of the iacH promoter. Sequence analysis and an electrophoretic mobility shift assay indicated that recombinant IacR binds specifically to a sequence with dyad symmetry in the iacR-iacH overlapping promoters in the absence of IAA. In addition, a two-plasmid expression system in Escherichia coli showed that IAA probably serves as a ligand that binds to IacR and releases it from the iacH promoter, thereby allowing RNA polymerase to transcribe iac. Thus, iac is expressed in order to promote IAA degradation, whereas free IacR is required for iac repression. We conclude that IacR serves as a key regulator of IAA degradation in A. baumannii in the rhizosphere. These results provide new insights into the possible role of A. baumannii in the environment. PMID:25726082

We examined how adsorption and desorption of gases from inlets and a cell could affect the accuracy of closed-cell FTIR measurements of carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), nitric oxide (NO), nitrogen dioxide (NO2), methanol (CH3OH), aceticacid (CH3COOH), and ammonia (NH3). When standards were delivered to the cell through a stainless steel inlet, temporarily reduced transmission was observed for CH3OH and NH3. However, a halocarbon wax coated inlet (normally used on the system) had excellent transmission (comparable to room temperature Teflon) for both CH3OH and NH3, even at temperatures as low as 5°C. Thus the wax is valuable for coating sampling system components that cannot be fashioned from Teflon. The instrument had a delayed response (˜10-40 s) for NH3 only, which was attributed to passivation of the Pyrex multipass cell. To determine sampling artifacts that could arise from the complex sample matrix presented by smoke, the closed-cell FTIR system was intercompared with an open-path FTIR system (which is immune to sampling artifacts) in well-mixed smoke. A similar cell passivation delay for NH3 was the only artifact found in this test. Overall, the results suggest that ˜10 s is sufficient to detect >80% of an NH3/CO ratio sampled by our fast-flow, closed-cell system. Longer sampling times or consecutive samples return better results. In field campaigns the closed-cell system sampling times were normally 10 to >100 s so NH3 was probably underestimated by 5-15%.

The antilisterial activity of monocaprylin (MC) and its combination with aceticacid (AA) on frankfurters was investigated. Each frankfurter was surface inoculated with a three-strain mixture of Listeria monocytogenes to obtain an inoculation level of 4.0 log CFU per frankfurter, and then dipped for 35 s in sterile deionized water (45 or 50 degrees C) containing 1% ethanol (control), 50 mM MC plus 1% ethanol, 1% AA plus 1% ethanol, or 50 mM MC plus 1% AA plus 1% ethanol. Samples were vacuum packaged, stored at 4 degrees C for 77 days, and analyzed for L. monocytogenes. Sensory odor and color of frankfurters were evaluated using a 9-point hedonic scale. Color was also objectively measured using the Minolta Chroma Meter. From day 0 to day 77, population counts of L. monocytogenes on frankfurters dipped in antimicrobial solutions at 50 degrees C were consistently lower than the control counts. Similar results were observed for samples treated at 45 degrees C. However, L. monocytogenes grew readily on control samples at both temperatures. Dipping of frankfurters in antimicrobial solutions (45 or 50 degrees C) significantly reduced (P < 0.05) the populations of L. monocytogenes. After 70 days of storage, L. monocytogenes was completely killed in samples dipped in MC+AA solution at 50 degrees C. The antimicrobial treatments did not affect the odor or color of the samples (P > 0.05). Overall, results indicated that dipping of frankfurters with MC reduced L. monocytogenes, and inclusion of AA further enhanced MC antilisterial activity, without any negative effect on odor or color. PMID:17685330

Green tea contains polyphenolic catechins that have been demonstrated to effectively inhibit Staphylococcus aureus and related bacteria. This study aimed to determine if home-brewed green tea could inhibit S. aureus through paper disk diffusion and minimum inhibitory concentration experiments. It was hypothesized that green tea brewed for varying periods of time in solutions with ascorbic acid, aceticacid, and sodium

Auxin is a pivotal plant hormone that regulates many aspects of plant growth and development. Auxin signaling is also known to promote plant disease caused by plant pathogens. However, the mechanism by which this hormone confers susceptibility to pathogens is not well understood. Here, we present evidence that fungal and bacterial plant pathogens hijack the host auxin metabolism in Arabidopsis thaliana, leading to the accumulation of a conjugated form of the hormone, indole-3-aceticacid (IAA)-Asp, to promote disease development. We also show that IAA-Asp increases pathogen progression in the plant by regulating the transcription of virulence genes. These data highlight a novel mechanism to promote plant susceptibility to pathogens through auxin conjugation. PMID:22374398

We study the growth of different isolates of Botrytis cinerea collected from potted plants which were affected by Botrytis blight in southern Spain during recent years. These isolates, which show widely phenotypic differences when grown in vitro, are differentially affected by growth temperature, gibberellic acid applications and paclobutrazol, an efficient plant growth retardant and fungicide at the same time. In this work, we have evaluated the effect of the auxin indole-3-aceticacid (IAA) dose (0, 1, 10, and 100 mg/plate) on the growth of the collection of B. cinerea isolates obtained from the following potted plants: Cyclamen persicum, Hydrangea macrophylla, Lantona camara, and Lonicera japonica. B. cinerea produces indolacetic acid, but so far the precise biosynthetic pathway and some effects on this fungal species are still unclear, although recent studies have revealed an antifungal activity of IAA on several fungi, including B. cinerea isolated from harvested fruits. Mycelial growth curves and growth rates assessed from difference in colony areas during the both linear and deceleration phase, conidiation (measured as time of appearance), conidia length (microm), and sclerotia production (number/plate) were evaluated in the isolates, which were grown at 26 degrees C on Petri dishes containing potato dextrose agar for up to 35 days. Mycelial growth curves fitted a typical kinetic equation of fungi grown on solid media. B. cinerea isolates showed a high degree of variability in their growth kinetics, depending on the isolate and auxin dose. This plant growth substance delayed mycelial growth during the linear phase in an isolate-dependent manner, thus isolates from C. persicum, H. macrophylla and L. camara were more affected by IAA than L. japonica. On the other hand, 100 mg of IAA was the critical dose to significantly reduce the growth rate in all isolates and to promote brown-striped hyphae development, especially in isolate from C. persicum. 10 and 100 mg IAA delayed conidiation in isolates from H. macrophylla but scarcely effects were found in the conidia length. The sclerotia production process was blocked at IAA doses of 100 mg in isolates from L. camara and L. japonica, and was reduced in isolate from H. macrophylla. However, dose of 100 mg IAA had no effect on sclerotia production in isolate from C. persicum. It was concluded that the effect of IAA on B. cinerea growth depends on the isolate, thus isolates from H. macrophylla and L. camara were the most affected by IAA. B. cinerea reduced its development under IAA applications, depending on the isolate and dose. These results confirm those recently published on the inhibitory effect of IAA on Botrytris species growth. PMID:22702183

Background Overproduction of free radicals and decreased antioxidant capacity are well-known risk factors for inflammatory bowel diseases. Gymnema sylvestre (GS) leaves extract is distinguished for its anti-diabetic, antioxidant and anti-inflammatory properties. Present study is designed to evaluate the preventative activities of GS against aceticacid (AA)-induced ulcerative colitis in Wistar rats. Methods Experimentally ulcerative colitis (UC) was induced by AA in animals pretreated with three different doses of GS leaves extract (50, 100, 200 mg/kg/day) and a single dose of mesalazine (MES, 300 mg/kg/day) for seven days. Twenty four hours later, animals were sacrificed and the colonic tissues were collected. Colonic mucus content was determined using Alcian blue dye binding technique. Levels of thiobarbituric acid reactive substances (TBARS), total glutathione sulfhydryl group (T-GSH) and non-protein sulfhydryl group (NPSH) as well as the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were estimated in colon tissues. Colonic nucleic acids (DNA and RNA) and total protein (TP) concentrations were also determined. Levels of pro-inflammatory cytokines including interleukin-1 beta (IL-1?), tumor necrosis factor-alpha (TNF-?) and interleukin-6 (IL-6) as well as prostaglandin E2 (PGE2) and nitric oxide (NO) were estimated in colonic tissues. The histopathological changes of the colonic tissues were also observed. Results In AA administered group TBARS levels were increased, while colonic mucus content, T-GSH and NP-SH, SOD and CAT were reduced in colon. Pretreatment with GS inhibited TBARS elevation as well as mucus content, T-GSH and NP-SH reduction. Enzymatic activities of SOD and CAT were brought back to their normal levels in GS pretreated group. A significant reduction in DNA, RNA and TP levels was seen following AA administration and this inhibition was significantly eliminated by GS treatment. GS pretreatment also inhibited AA-induced elevation of pro-inflammatory cytokines, PGE2 and NO levels in colon. The apparent UC protection was further confirmed by the histopathological screening. Conclusion The GS leaves extract showed significant amelioration of experimentally induced colitis, which may be attributed to its anti-inflammatory and antioxidant property. PMID:24507431

A small amount of nitrate, ~0.002 molal, initiates the Co/Mn catalyzed aerobic oxidation of bromide compounds (HBr,NaBr,LiBr) to dibromine in aceticacid at room temperature. At temperatures 40oC or less , the reaction is autocatalytic. Co(II) and Mn(II) themselves and mixed with ionic bromide are known homogeneous oxidation catalysts. The reaction was discovered serendipitously when a Co/Br and Co/Mn/Br catalyst solution was prepared for the aerobic oxidation of methyaromatic compounds and the Co acetate contained a small amount of impurity i.e. nitrate. The reaction was characterized by IR, UV-VIS, MALDI and EXAFS spectroscopies and the coordination chemistry is described. The reaction is inhibited by water and its rate changed by pH. The change in these variables, as well as others, are identical to those observed during homogeneous, aerobic oxidation of akylaromatics. A mechanism is proposed. Accidental addition of a small amount of nitrate compound into a Co/Mn/Br/aceticacid mixture in a large, commercial feedtank is potentially dangerous.

The title triterpene, D-friedoolean-14-en-3 beta-yl acetate, C32H52O2, was isolated from dichloromethane extracts of the roots of common ragweed Ambrosia artemisiifolia. The skeleton contains five fused six-membered rings with an average Csp3-Csp3 bond distance of 1.549 (6) A and one double bond of length 1.348 (6) A. The D and E rings are cis-fused. The compound also contains a beta-oriented acetate group with a C-O distance 1.461 (5) A. PMID:10641284

This work investigated the feasibility of recovering and concentrating sugars and aceticacid (HAc) from prehydrolysis liquor (PHL) of the kraft-based dissolving pulp process prior to fermentation of hemicellulosic sugars, by the combination of activated carbon adsorption, nanofiltration (NF) and reverse osmosis (RO) processes. To reduce the fouling PHL was subjected to adsorption on activated carbon, then the treated PHL (TPHL) passed through a nanofiltration (NF DK) membrane to retain the sugars, and the permeate of aceticacid rich solution was passed through a reverse osmosis membrane (RO SG). It was found that for NF process sugars were concentrated from 48 to 227g/L at a volume reduction factor (VRF) of 5 while 80 to 90% of aceticacid was permeated. For the reverse osmosis process, 68% of aceticacid retention was achieved at pH 4.3 and 500 psi pressure and the HAc concentration increased from 10 to 50g/L. PMID:24434701

Succinimide formation from aspartic acid (Asp) residues is a concern in the formulation of protein drugs. Based on density functional theory calculations using Ace-Asp-Nme (Ace = acetyl, Nme = NHMe) as a model compound, we propose the possibility that aceticacid (AA), which is often used in protein drug formulation for mildly acidic buffer solutions, catalyzes the succinimide formation from Asp residues by acting as a proton-transfer mediator. The proposed mechanism comprises two steps: cyclization (intramolecular addition) to form a gem-diol tetrahedral intermediate and dehydration of the intermediate. Both steps are catalyzed by an AA molecule, and the first step was predicted to be rate-determining. The cyclization results from a bond formation between the amide nitrogen on the C-terminal side and the side-chain carboxyl carbon, which is part of an extensive bond reorganization (formation and breaking of single bonds and the interchange of single and double bonds) occurring concertedly in a cyclic structure formed by the amide NH bond, the AA molecule and the side-chain C=O group and involving a double proton transfer. The second step also involves an AA-mediated bond reorganization. Carboxylic acids other than AA are also expected to catalyze the succinimide formation by a similar mechanism. PMID:25588215

Organic acids, central to terrestrial carbon metabolism and atmospheric photochemistry, are ubiquitous in the troposphere in the gas, particle, and aqueous phases. As the dominant organic acids in the atmosphere, formic acid (FA, HCOOH) and aceticacid (AA, CH3COOH) control precipitation acidity in remote regions and may represent a critical link between the terrestrial carbon and water cycles by acting as key intermediates in plant carbon and energy metabolism and aerosol-cloud-precipitation interactions. However, our understanding of the exchange of these acids between terrestrial ecosystems and the atmosphere is limited by a lack of field observations, the existence of biogenic and anthropogenic primary and secondary sources whose relative importance is unclear, and the fact that vegetation can act as both a source and a sink. Here, we first present data obtained from the tropical rainforest mesocosm at Biosphere 2 which isolates primary vegetation sources. Strong light and temperature dependent emissions enriched in FA relative to AA were simultaneously observed from individual branches (FA/AA = 3.0 ± 0.7) and mesocosm ambient air (FA/AA = 1.4 ± 0.3). We also present long-term observations of vertical concentration gradients of FA and AA within and above a primary rainforest canopy in the central Amazon during the 2010 dry and 2011 wet seasons. We observed a seasonal switch from net ecosystem-scale deposition during the dry season to net emissions during the wet season. This switch was associated with reduced ambient concentrations in the wet season (FA < 1.3 nmol mol-1, AA < 2.0 nmol mol-1) relative to the dry season (FA up to 3.3 nmol mol-1, AA up to 6.0 nmol mol-1), and a simultaneous increase in the FA/AA ambient concentration ratios from 0.3-0.8 in the dry season to 1.0-2.1 in the wet season. These observations are consistent with a switch between a biomass burning dominated source in the dry season (FA/AA < 1.0) to a vegetation dominated source in the wet season (FA/AA > 1.0). Our observations provide the first ecosystem-scale evidence of bidirectional FA and AA exchange between a forest canopy and the atmosphere controlled by ambient concentrations and ecosystem scale compensation points (estimated to be 1.3 ± 0.3 nmol mol-1: FA, and 2.1 ± 0.4 nmol mol-1: AA). These results suggest the need for a fundamental change in how future biosphere-atmosphere exchange models should treat FA and AA with a focus on factors that influence net exchange rates (ambient concentrations and ecosystem compensation points) rather than treating emissions and deposition separately.

Organic acids, central to terrestrial carbon metabolism and atmospheric photochemistry, are ubiquitous in the troposphere in the gas, particle, and aqueous phases. As the dominant organic acids in the atmosphere, formic acid (FA, HCOOH) and aceticacid (AA, CH3COOH) control precipitation acidity in remote regions and may represent a critical link between the terrestrial carbon and water cycles by acting as key intermediates in plant carbon and energy metabolism and aerosol-cloud-precipitation interactions. However, our understanding of the exchange of these acids between terrestrial ecosystems and the atmosphere is limited by a lack of field observations, the existence of biogenic and anthropogenic primary and secondary sources whose relative importance is unclear, and the fact that vegetation can act as both a source and a sink. Here, we first present data obtained from the tropical rainforest mesocosm at Biosphere 2 which isolates primary vegetation sources. Strong light and temperature dependent emissions enriched in FA relative to AA were simultaneously observed from individual branches (FA/AA = 2.1 ± 0.6) and mesocosm ambient air (FA/AA = 1.4 ± 0.3). We also present long-term observations of vertical concentration gradients of FA and AA within and above a primary rainforest canopy in the central Amazon during the 2010 dry and 2011 wet seasons. We observed a seasonal switch from net ecosystem-scale deposition during the dry season to net emissions during the wet season. This switch was associated with reduced ambient concentrations in the wet season (FA < 1.3 nmol mol-1, AA < 2.0 nmol mol-1) relative to the dry season (FA up to 3.3 nmol mol-1, AA up to 6.0 nmol mol-1), and a simultaneous increase in the FA/AA ambient concentration ratios from 0.3-0.8 in the dry season to 1.0-2.1 in the wet season. These observations are consistent with a switch between a biomass burning dominated source in the dry season (FA/AA < 1.0) to a vegetation dominated source in the wet season (FA/AA > 1.0). Our observations provide the first ecosystem-scale evidence of bidirectional FA and AA exchange between a forest canopy and the atmosphere controlled by ambient concentrations and ecosystem scale compensation points (estimated to be 1.3 nmol mol-1: FA, and 2.1 nmol mol-1: AA). These results suggest the need for a fundamental change in how future biosphere-atmosphere exchange models should treat FA and AA with a focus on factors that influence net exchange rates (ambient concentrations and ecosystem compensation points) rather than treating emissions and deposition separately.

Organic acids, central to terrestrial carbon metabolism and atmospheric photochemistry, are ubiquitous in the troposphere in the gas, particle, and aqueous phases. As the dominant organic acids in the atmosphere, formic acid (FA, HCOOH) and aceticacid (AA, CH3COOH) control precipitation acidity in remote regions and may represent a critical link between the terrestrial carbon and water cycles by acting as key intermediates in plant carbon and energy metabolism and aerosol-cloud-precipitation interactions. However, our understanding of the exchange of these acids between terrestrial ecosystems and the atmosphere is limited by a lack of field observations, the existence of biogenic and anthropogenic primary and secondary sources whose relative importance is unclear, and the fact that vegetation can act as both a source and a sink. Here, we present results from the tropical rainforest mescosom at Biosphere 2 which isolates primary vegetation sources. Strong light and temperature dependent emissions of FA and AA were simultaneously observed from individual branches and mesocosm ambient air with a strong enrichment in FA (FA/AA = 1.4 +/- 0.3, R2 of 0.89 +/- 0.10). We also present long-term observations of vertical concentration gradients of FA and AA within and above a primary rainforest canopy in central Amazonia during the 2010 dry and 2011 wet seasons. We observed a seasonal switch from net ecosystem-scale deposition during the dry season to net emissions during the wet season. This switch was associated with reduced ambient concentrations in the wet season (FA < 1.3 ppbv, AA < 2.0 ppbv) relative to the dry season (FA up to 3.3 ppbv, AA up to 6.0 ppbv), and a simultaneous increase in the FA/AA ambient concentration ratios from 0.3-0.8 in the dry season to 1.0-2.1 in the wet season. These observations are consistent with a switch between a biomass burning dominated source in the dry season (FA/AA < 1.0) to a vegetation dominated source in the wet season and call into question the view that secondary production of FA and AA from biogenic precursors like isoprene are the largest atmospheric source. Our observations provide the first ecosystem-scale evidence of bidirectional FA and AA exchange between a forest canopy and the atmosphere controlled by ambient concentrations and ecosystem scale compensation points (estimated to be 1.3 ppbv: FA, and 2.1 ppbv: AA). These results suggest the need for a fundamental change in how future biosphere-atmosphere exchange models should treat FA and AA with a focus on factors that influence net exchange rates (ambient concentrations and ecosystem compensation points) rather than treating emissions and deposition separately.

Germinating seed ofDalbergia dolichopetala converted both [2H5]l-tryptophan and [2H5]indole-3-ethanol to [2H5]indole-3-aceticacid (IAA). Metabolism of [2'-14C]IAA resulted in the production of indole-3-acetylaspartic acid (IAAsp), as well as several unidentified components, referred to as metabolites I, II, IV and V. Re-application of [14C]IAAsp to the germinating seed led to the accumulation of the polar, water-soluble compound, metabolite V, as the major

This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85.degree. and 200.degree. C. and removing the reaction products from the contact zone.

Background Ulcerative colitis is a chronic inflammatory disease and involves multiple etiological factors. Aceticacid (AA)-induced colitis is a reproducible and simple model, sharing many characteristics with human colitis. N-acetylcysteine (NAC) has been widely used as an antioxidant in vivo and in vitro. NAC can affect several signaling pathways involving in apoptosis, angiogenesis, cell growth and arrest, redox-regulated gene expression, and inflammatory response. Therefore, NAC may not only protect against the direct injurious effects of oxidants, but also beneficially alter inflammatory events in colitis. This study was conducted to investigate whether NAC could alleviate the AA-induced colitis in a porcine model. Methods Weaned piglets were used to investigate the effects of NAC on AA-induced colitis. Severity of colitis was evaluated by colon histomorphology measurements, histopathology scores, tissue myeloperoxidase activity, as well as concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon. The protective role of NAC was assessed by measurements of antioxidant status, growth modulator, cell apoptosis, and tight junction proteins. Abundances of caspase-3 and claudin-1 proteins in colonic mucosae were determined by the Western blot method. Epidermal growth factor receptor, amphiregulin, tumor necrosis factor-alpha (TNF-?), and toll-like receptor 4 (TLR4) mRNA levels in colonic mucosae were quantified using the real-time fluorescent quantitative PCR. Results Compared with the control group, AA treatment increased (P?0.05) the histopathology scores, intraepithelial lymphocyte (IEL) numbers and density in the colon, myeloperoxidase activity, the concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon, while reducing (P?0.05) goblet cell numbers and the protein/DNA ratio in the colonic mucosa. These adverse effects of AA were partially ameliorated (P?0.05) by dietary supplementation with NAC. In addition, NAC prevented the AA-induced increase in caspase-3 protein, while stimulating claudin-1 protein expression in the colonic mucosa. Moreover, NAC enhanced mRNA levels for epidermal growth factor and amphiregulin in the colonic mucosa. Conclusion Dietary supplementation with NAC can alleviate AA-induced colitis in a porcine model through regulating anti-oxidative responses, cell apoptosis, and EGF gene expression. PMID:24001404

Atopic dermatitis (AD) and allergic contact dermatitis (ACD) are common allergic and inflammatory skin diseases caused by a combination of eczema, scratching, pruritus, and cutaneous sensitization with allergens. This paper examines whether oleanolic acidacetate (OAA) modulates AD and ACD symptoms by using an existing AD model based on the repeated local exposure of mite extract (Dermatophagoides farinae extract, DFE) and 2,4-dinitrochlorobenzene to the ears of BALB/c mice. In addition, the paper uses a 2,4-dinitrofluorobenzene-sensitized local lymph node assay (LLNA) for the ACD model. The oral administration of OAA over a four-week period attenuated AD symptoms in terms of decreased skin lesions, epidermal thickness, the infiltration of immune cells (CD4{sup +} cells, eosinophils, and mast cells), and serum IgE, IgG2a, and histamine levels. The gene expression of Th1, Th2, Th17, and Th22 cytokines was reduced by OAA in the lymph node and ear tissue, and the LLNA verified that OAA suppressed ACD. The oral administration of OAA over a three-day period attenuated ACD symptoms in terms of ear thickness, lymphocyte proliferation, and serum IgG2a levels. The gene expression of Th1, Th2, and Th17 cytokines was reduced by OAA in the thymus and ear tissue. Finally, to define the underlying mechanism, this paper uses a TNF-?/IFN-?-activated human keratinocyte (HaCaT) model. OAA inhibited the expression of cytokines and chemokines through the downregulation of NF-?B and MAPKs in HaCaT cells. Taken together, the results indicate that OAA inhibited AD and ACD symptoms, suggesting that OAA may be effective in treating allergic skin disorders. - Highlights: • OAA reduced both acute and chronic AD symptoms. • OAA had a controlling effect on the immune reaction for ACD. • The effect of OAA on allergic skin disorders was comparable to the cyclosporine A. • OAA might be a candidate for the treatment of allergic skin disorders.

The most important pathogen for table grapes is Botrytis cinerea which causes a rapid deterioration of fruit. Postharvest losses are controlled with SO2 fumigations carried out every 7 or 10 days, but the use of this gas is becoming more difficult to justify because of undesirable effects on the fruit and the increasing concern for human health. Aceticacid, classified as a GRAS compound, can be employed with no restriction as preservative and represents a possible substitute to sulphur dioxide. The aims of the present work were: (1) to evaluate if repeated treatments with AAC during storage preserve table grapes fruit quality; (2) to verify the effectiveness of 3 different concentrations and time intervals between each treatment and compare the effects with SO2 treatment; The amounts of AAC used in each fumigation, performed for 15 minutes, were 30, 50 and 75 microL/L, and treatments were carried out 5, 3 and 2 times respectively during storage, in order to have the same final concentration (150 microL/L). Table grapes were also fumigated with SO2. Fruit was stored for 8 weeks at 5 degrees C and 95% of RH, followed by 4 days of a simulated shelf-life (SSL) at 20 degrees C and 85% RH. At the end of experiment decay, weight loss and visual assessment were evaluated. After eight weeks of storage the incidence of grey mould, with respect to untreated fruit, was reduced in all treatments. The comparison among the different treatments did not show significant differences between the fumigations performed 3 and 2 times, with 24.9% and 27.2% of rots respectively. A better decay control was achieved with 5 fumigations carried out every 2 weeks, (18.1% of rots), while decay in fruit treated with SO2 was 26.2%. During the SSL period no particular differences were observed among all treatments. None of the treatments affected weight loss, as well as no differences were found in the score attributed for the external quality (rachis browning and berries appearance). The results showed that a good control of grey mould could be achieved on table grapes by repeated fumigations during storage. AAC could be a promising compound to be used as alternative to SO2 in keeping fruit quality. PMID:23878976

To investigate novel pathways involved in auxin biosynthesis, transport, metabolism, and response, we have developed a high-throughput screen for indole-3-aceticacid (IAA) levels. Historically, the quantitative analysis of IAA has been a cumbersome and time-consuming process that does not lend itself to the screening of large numbers of samples. The method described here can be performed with or without an automated liquid handler and involves purification solely by solid-phase extraction in a 96-well format, allowing the analysis of up to 96 samples per day. In preparation for quantitative analysis by selected ion monitoring-gas chromatography-mass spectrometry, the carboxylic acid moiety of IAA is derivatized by methylation. The derivatization of the IAA described here was also done in a 96-well format in which up to 96 samples can be methylated at once, minimizing the handling of the toxic reagent, diazomethane. To this end, we have designed a custom diazomethane generator that can safely withstand high flow and accommodate larger volumes. The method for IAA analysis is robust and accurate over a range of plant tissue weights and can be used to screen for and quantify other indolic auxins and compounds including indole-3-butyric acid, 4-chloro-indole-3-aceticacid, and indole-3-propionic acid. PMID:17889819

Rates of secretion of components into milk are a func- tion of precursor concentrations and parameters that describe expression of the milk synthetic enzymes and their sensitivity to precursor concentrations. To estab- lish the enzymatic sensitivities of milk fat yield and mammary acetate utilization to circulating acetate con- centration, lactating cows were infused for 10 h with 0 or 40

The acetate radical ion reacts with ozone with a rate constant of k = (1.5 +/- 0.5) x 10Z dmT mol s . The products from this reaction are CO2, HCHO, and O2 . By subsequent reaction of the peroxy radical with ozone the acetate radical ion is regenerated through the OH radical. A chain decomposition of ozone takes place. It terminates when the acetate radical ion reacts with oxygen forming the unreactive peroxy acetate radical. The chain is rather short as oxygen is developed, as a result of the ozone consumption. The inhibiting effect of acetate on the ozone decay is rationalized by OH scavenging by acetate and successive reaction of the acetate radical ion with oxygen. Some products from the bimolecular disappearance of the peroxy acetate radicals, however, react further with ozone, reducing the effectiveness of the stabilization.

We used self-assembling tunnel junctions (SATJs) to study the electron transport
through films of the molecular magnets, Mn12-Acetate. Pulse laser deposition
(PLD) was used to deposit two monolayers of Mn12-Acetate on ...

Measurements were made of the fresh weight, dry weight, dry weight-fresh weight ratio, free and conjugated indole-3-aceticacid, and free and conjugated abscisic acid in seedlings of Zea mays grown in darkness in microgravity and on earth. Imbibition of the dry kernels was 17 h prior to launch. Growth was for 5 d at ambient orbiter temperature and at a chronic accelerational force of the order of 3 x 10(-5) times earth gravity. Weights and hormone content of the microgravity seedlings were, with minor exceptions, not statistically different from seedlings grown in normal gravity. The tissues of the shuttle-grown plants appeared normal and the seedlings differed only in the lack of orientation of roots and shoots. These findings, based upon 5 d of growth in microgravity, cannot be extrapolated to growth in microgravity for weeks, months, and years, as might occur on a space station. Nonetheless, it is encouraging, for prospects of bioregeneration of the atmosphere and food production in a space station, that no pronounced differences in the parameters measured were apparent during the 5 d of plant seedling growth in microgravity.

The effect of different sources of nitrogen as well as their concentrations on the bioconversion of carbon monoxide to metabolic products such as aceticacid and ethanol by Clostridium autoethanogenum was studied. In a first set of assays, under batch conditions, either NH4Cl, trypticase soy broth or yeast extract (YE) were used as sources of nitrogen. The use of YE was found statistically significant (p < 0.05) on the product spectrum in such batch assays. In another set of experiments, three bioreactors were operated with continuous CO supply, in order to estimate the effect of running conditions on products and biomass formation. The bioreactors were operated under different conditions, i.e., EXP1 (pH = 5.75, YE 1g/L), EXP2 (pH = 4.75, YE 1 g/L) and EXP3 (pH = 5.75, YE 0.2 g/L). When compared to EXP2 and EXP3, it was found that EXP1 yielded the maximum biomass accumulation (302.4 mg/L) and products concentrations, i.e., aceticacid (2147.1 mg/L) and ethanol (352.6 mg/L). This can be attributed to the fact that the higher pH and higher YE concentration used in EXP1 stimulated cell growth and did, consequently, also enhance metabolite production. However, when ethanol is the desired end-product, as a biofuel, the lower pH used in EXP2 was more favourable for solventogenesis and yielded the highest ethanol/aceticacid ratio, reaching a value of 0.54. PMID:25608591

High sensitivity zinc oxide (ZnO) tetrapods (TPs) have been functionalized by nucleating cadmium sulphide (CdS) nanoparticles (NPs) directly on their surface with a spotted coverage thanks to an optimized synthesis in dimethylformamide (DMF). The obtained hybrid coupled material has been used to realize a gas sensing device with a highly porous nanostructured network, in which the proper alternation of ZnO-TPs and CdS-NPs gives rise to unconventional chemoresistive behaviours. Among the different tested gases and vapours, the sensor showed a unique fingerprint response-inversion between 300 °C and 400 °C only for nitrogen dioxide (NO2) and aceticacid (CH3COOH).

A method for the analysis of indole-3-aceticacid (IAA) in plant extracts has been developed based on high performance liquid chromatography separation of IAA on a microparticulate strong anion exchange column followed by quantitation with two selective detectors: an electrochemical, carbon paste amperometric detector and/or a fluorescence detector. The detection limit for IAA is less than 1 nanogram with the fluorescence detector and less than 50 picograms with the electrochemical detector. The IAA levels are reported for various tissues of wheat, pinto beans, soybeans, cotton, and corn. PMID:16660271

A new tridentate ligand, [(2-hydroxy-3,5-diiodo-benzylidene)-amino]-aceticacid (HDBA), has been synthesized from 3,5-diiodosalicylaldehyde and glycine in ethanol. A 1-D coordination polymer has been synthesized by reaction of HDBA with Cu(Ac)2 · H2O in ethanol–water. The complex was characterized by UV, IR, ESI–MS, elemental analyses, and X-ray crystallography. The central copper(II) is five-coordinate by one nitrogen and two oxygens from HDBA, one

A toxicologic and dermatologic review of ?-methylbenzyl acetate when used as a fragrance ingredient is presented. ?-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for ?-methylbenzyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, and repeated dose data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22406576

A toxicologic and dermatologic review of benzyl acetate when used as a fragrance ingredient is presented. Benzyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for benzyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, phototoxicity, toxicokinetics, repeated dose, reproductive toxicity, genotoxicity, or carcinogenicity data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Refer Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22387848

...ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a...additive lead acetate may be safely used in cosmetics intended for coloring hair on the scalp...The amount of the lead acetate in the cosmetic shall be such that the lead...

...ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a...additive lead acetate may be safely used in cosmetics intended for coloring hair on the scalp...The amount of the lead acetate in the cosmetic shall be such that the lead...

The effect of adding a third metal (Ni, Co, Pd, Rh) to Pt-Sn/C catalyst has been investigated for the adsorption and oxidation of aceticacid in acidic medium using in situ Fourier transform infrared (FTIR) spectroscopy. The results showed that the decomposition of aceticacid on the surface leads to the formation of different intermediate species and products such as acetate, acetyl, carbonate, CO and CO2. The reaction pathway of CO2 production proceeds via the formation of acetyl or carbonate through surface acetate species. It has been found that the selectivity of the acetate was enhanced by the addition of any third metal. However, the presence of Pd or Co increases the relative intensity of IR band for CO2. This is probably due to success in facilitating of the Csbnd C bond cleavage of acetyl. On the other hand, the conversion of acetate to carbonate is strongly affected by the adsorbed water, as is evident from the pronounced changes in the OH stretching region with the presence of Pd or Ni.

Objectives To determine if, in the short term, aceticacid and dexamethasone iontophoresis combined with LowDye (low?Dye) taping are effective in treating the symptoms of plantar fasciitis. Methods A double blinded, randomised, placebo controlled trial of 31 patients with medial calcaneal origin plantar fasciitis recruited from three sports medicine clinics. All subjects received six treatments of iontophoresis to the site of maximum tenderness on the plantar aspect of the foot over a period of two weeks, continuous LowDye taping during this time, and instructions on stretching exercises for the gastrocnemius/soleus. They received 0.4% dexamethasone, placebo (0.9% NaCl), or 5% aceticacid. Stiffness and pain were recorded at the initial session, the end of six treatments, and the follow up at four weeks. Results Data for 42 feet from 31 subjects were used in the study. After the treatment phase, all groups showed significant improvements in morning pain, average pain, and morning stiffness. However for morning pain, the aceticacid/taping group showed a significantly greater improvement than the dexamethasone/taping intervention. At the follow up, the treatment effect of aceticacid/taping and dexamethasone/taping remained significant for symptoms of pain. In contrast, only aceticacid maintained treatment effect for stiffness symptoms compared with placebo (p ?=? 0.031) and dexamethasone. Conclusions Six treatments of aceticacid iontophoresis combined with taping gave greater relief from stiffness symptoms than, and equivalent relief from pain symptoms to, treatment with dexamethasone/taping. For the best clinical results at four weeks, taping combined with aceticacid is the preferred treatment option compared with taping combined with dexamethasone or saline iontophoresis. PMID:16488901

Microbiological safety has been a critical issue for acid and acidified foods since it became clear that acid-tolerant pathogens such as Escherichia coli O157:H7 can survive (even though they are unable to grow) in a pH range of 3 to 4, which is typical for these classes of food products. The primary antimicrobial compounds in these products are aceticacid and NaCl, which can alter the intracellular physiology of E. coli O157:H7, leading to cell death. For combinations of aceticacid and NaCl at pH 3.2 (a pH value typical for non-heat-processed acidified vegetables), survival curves were described by using a Weibull model. The data revealed a protective effect of NaCl concentration on cell survival for selected aceticacid concentrations. The intracellular pH of an E. coli O157:H7 strain exposed to aceticacid concentrations of up to 40 mM and NaCl concentrations between 2 and 4% was determined. A reduction in the intracellular pH was observed for increasing aceticacid concentrations with an external pH of 3.2. Comparing intracellular pH with Weibull model predictions showed that decreases in intracellular pH were significantly correlated with the corresponding times required to achieve a 5-log reduction in the number of bacteria. PMID:21115706

Objectives: To evaluate the effect of ethanolic extract of leaves of Paederia foetida on aceticacid induced colitis in albino rats. Materials and Methods: Ethanolic extract of Paederia foetida (EEPF) was prepared by percolation method. Acute toxicity test was done by using Organization for Economic Cooperation and Development guidelines. Albino rats were divided into four groups of five animals each. Groups A and B received 3% gum acacia. Groups C and D received EEPF 500 mg/kg body weight (BW) and 5-aminosalisylic acid 100 mg/kg BW respectively. Colitis was induced by transrectal administration of 4% aceticacid on 5th day. All animals were sacrificed after 48 h of colitis induction and distal 10 cm of the colon was dissected. Colon was weighed for disease activity index (DAI) and scored macroscopically and microscopically. Biochemical assessment of tissue myeloperoxidase (MPO), catalase (CAT) and superoxide dismutase (SOD) was done in colonic tissue homogenate and malondialdehyde (MDA) was estimated in serum. Results: P. foetida showed significant (P < 0.05) reduction in DAI, macroscopic and microscopic lesion score as well as significant (P < 0.05) improvement in MPO, MDA, CAT, and SOD level as compared to Group B. Conclusions: The ethanolic extract of leaves of P. foetida showed significant amelioration of experimentally induced colitis, which may be attributed to its anti-inflammatory and antioxidant property. PMID:24130378

The first asymmetric cyclopropanation of ketene silyl acetal with allylic acetate was achieved. New chiral oxazolidinylpyrazole ligands and their ?3-allylpalladium complexes were synthesized. Reaction of cinnamyl acetate with ketene silyl acetal of ethyl isobutylate in the presence of a palladium complex gave a phenyl cyclopropane derivative in 20? 54%ee.

Ladybird beetles produce a large number of defensive alkaloids. Previous studies suggest that the structural diversity of these endogenous alkaloids can be traced to a common biosynthetic route based on the condensation of several acetate units. In this study, adults of Epilachna paenulata, a phytophagous neotropical species, were fed on diet enriched with potential precursors (sodium acetate, fatty acids and the amino acids lysine and ornithine) labeled with stable isotopes ((13)C, (2)H and (15)N). Labeled acetate was incorporated into the structurally related homotropane and piperidine alkaloids. The later also showed incorporation of [methyl-(2)H3] stearic acid. Our results hence support a fatty acid pathway for the biosynthesis of E. paenulata alkaloids. To our knowledge, this is the first report on the incorporation of a labeled fatty acid into a defensive piperidine alkaloid in insects. PMID:22062684

The polar transport of the natural auxins indole-3-butyric acid (IBA) and indole-3-aceticacid (IAA) has been described in Arabidopsis (Arabidopsis thaliana) hypocotyls using radioactive tracers. Because radioactive assays alone cannot distinguish IBA from its metabolites, the detected transport from applied [3H]IBA may have resulted from the transport of IBA metabolites, including IAA. To test this hypothesis, we used a mass spectrometry-based method to quantify the transport of IBA in Arabidopsis hypocotyls by following the movement of [13C1]IBA and the [13C1]IAA derived from [13C1]IBA. We also assayed [13C6]IAA transport in a parallel control experiment. We found that the amount of transported [13C1]IBA was dramatically lower than [13C6]IAA, and the IBA transport was not reduced by the auxin transport inhibitor N-1-naphthylphthalamic acid. Significant amounts of the applied [13C1]IBA were converted to [13C1]IAA during transport, but [13C1]IBA transport was independent of IBA-to-IAA conversion. We also found that most of the [13C1]IBA was converted to ester-linked [13C1]IBA at the apical end of hypocotyls, and ester-linked [13C1]IBA was also found in the basal end at a level higher than free [13C1]IBA. In contrast, most of the [13C6]IAA was converted to amide-linked [13C6]IAA at the apical end of hypocotyls, but very little conjugated [13C6]IAA was found in the basal end. Our results demonstrate that the polar transport of IBA is much lower than IAA in Arabidopsis hypocotyls, and the transport mechanism is distinct from IAA transport. These experiments also establish a method for quantifying the movement of small molecules in plants using stable isotope labeling. PMID:22323783

It has been reported that auxin induces an epinastic growth response in plant leaf tissues. Leaf strips of tobacco (Nicotiana tabacum L. 'Bright Yellow 2') were used to study the effects of indole-3-aceticacid (IAA), the prin- cipal form of auxin in higher plants, and a synthetic auxin, 2,4-dichlorophenoxyacetic acid (2,4-D), on epinastic leaf curvature. Incubation of leaf strips with

Wet-only deposition samples were collected at a site in the urban area of the São Paulo metropolis between February (end of the rainy summer) and October (beginning of spring) 2000, an atypical period due to rainfall 40% below the 30-year average. The majority ions in rainwater were measured by capillary zone electrophoresis with contactless conductivity detection, CZE-CCD, applied for the first time to the organic anions acetate and formate. The volume weight mean (VWM) concentrations of the majority anions NO 3-, SO 42- and Cl - were, respectively, 15.6, 9.5 and 4.7 ?mol l -1. The VWM concentration of HCOO -t, (HCOO -+HCOOH) was 17.0 ?mol l -1, about twice the 8.9 ?mol l -1 of CH 3COO -t. The VWM concentration of free H + was low ( 16.9 ?mol l -1), corresponding to pH 4.77. This denotes the relevance of species like ammonia, analyzed as NH4+ ( VWM=27.9 ?mol l -1), and calcium carbonate ( VWM=5.3 ?mol l -1 Ca2+) as partial neutralizers of the acidity. By hypothetically assuming that H + is the only counterion of the non-sea-salt fraction of the dissociated anions, their contribution to the total potential acidity would decrease in the following order: sulfate (29%), formate (29%), nitrate (26%), acetate (15%) and chloride (1%). The 44% potential participation of the carboxylic acids reveals their importance to the acidity of São Paulo's rainwater during the study period. Direct vehicular emission of lower carboxylic acids and aldehydes (in particular, aceticacid and acetaldehyde) is singularly high in the metropolis due to the extensive use of ethanol and gasohol (containing ˜20% of ethanol) as fuels of the light fleet of 5.5 million cars; in addition, regional atmospheric conditions favor the photochemical formation of the acids, since concentrations of ozone and aldehydes are high and solar irradiation is intense at the 23°34'S latitude. The presence of higher concentrations of HCOOH than CH 3COOH indicates a prevalence of its photochemical production by H 2CO oxidation in the atmosphere.

Ulcerative colitis (UC) is a chronic disease that causes an inflammatory condition in the colon. Several cytokines, including tumor necrosis factor alpha (TNF-?), interleukin 1 beta (IL-1?) and transforming growth factor beta (TGF-?) are crucial components of these inflammatory pathways. New therapeutic strategies are needed for improved clinical outcomes in UC and with less adverse effects. That is why alternative therapies such as herbal remedies are increasingly being used with favorable effects in the treatment of UC. Hence, in the present study, we aimed to evaluate the protective effect of Echinacea spp in an experimental rat colitis model induced by aceticacid (AA). Aceticacid was given via a rectal route to induce acute colitis in rats. Rats were placed in four groups: control, Echinacea, Echinacea-colitis and colitis. Tumor necrosis factor alpha, IL-1? and TGF-? levels were measured. Histopathological comparison of the groups was also performed. The disease activity index (DAI) was significantly higher in the colitis group compared to the control, Echinacea and Echinacea-colitis groups (p<0.001). There was no significant difference between the DAI of control, Echinacea and Echinacea-colitis groups (p>0.07). The inflammatory mediators IL-1? and TNF-? were significantly elevated in the colitis group compared to the other groups (p<0.007, <0.001 respectively). Therefore, Echinacea spp. may likely have some therapeutic favorable effects in the management of UC. PMID:25362606

In this study, we examined rabbit gastric ulcer models that can serve as more clinically relevant models. Two types of ulcer model were studied: aceticacid-induced ulcers (AAU) and mucosal resection-induced ulcers (MRU). For AAU, rabbit gastric mucosa was exposed by median laparotomy and treated with bottled aceticacid. MRU was examined as a model for endoscopic mucosal resection (EMR). Normal saline was injected into the submucosal layer and the swollen mucosa was resected with scissors. Endoscopic mucosal resection (EMR) is frequently performed for treatment of early gastric cancers. This procedure inevitably leads to ulcers and bleeding. Bleeding control is the major concern in endoscopic mucosectomy, and some endoscopic hemostatic agents are currently under clinical and preclinical studies. MRU was developed as a model for these induced ulcers and the evaluation of the healing process. The clinical relevancy of those models was compared with that of rat models. Progressive healing was observed for 7 days based on histology. Rabbit models demonstrate round, deep ulcers with clear margins and well-defined healing stages that were difficult to define in rat models. PMID:23825482

Several fractions of proteolipids from Torpedo electroplax were separated by DEAE-cellulose chromatography in organic solvents, and the sulphydryl groups were determined by a spectrophotometric method. On the same fractions the covalent labeling with iodo-(/sup 3/H)aceticacid to sulphydryl groups was studied. In total proteolipids there were 30.3 nmol/mg protein of sulphydryl groups of which 20.6 nmoles were in the form of disulfide bonds and 10.9 nmol as free--SH groups. The highest content of sulphydryl groups (36.7 nmol/mg protein) was found in fraction II; while fraction I, that binds the cholinergic ligands, has a lower content (23.7 nmol/mg protein). The 42 Kdaltons polypeptide, which is the major band in Fraction II, has the strongest labeling with iodo-(/sup 3/H)aceticacid, while the 39 Kdaltons cholinergic polypeptide shows a lower labeling. The importance of proteolipids as channel-forming macromolecules is discussed in connection with the possible significance of the 42 Kdaltons polypeptide.

Due to their remarkable antibacterial/antivirus properties, silver nanoparticles (Ag NPs) and zinc oxide quantum dots (ZnO Qds) have been widely used in the antimicrobial field. The mechanism of action of Ag NPs on bacteria was recently studied and it has been proven that Ag NPs exerts their antibacterial activities mainly by the released Ag+. In this work, Ag NPs and ZnO Qds were synthesized using polyol and hydrothermal method, respectively. It was demonstrated that Ag NPs can be oxidized easily in aqueous solution and the addition of aceticacid can increase the Ag+ release which improves the antibacterial activity of Ag NPs. A comparative study between bactericidal effect of Ag NPs/aceticacid and Ag NPs/ZnO Qds on Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia and Staphylococcus aureus was undertaken using agar diffusion method. The obtained colloids were characterized using UV-vis spectroscopy, Raman spectrometry, X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM).

The ration fed to laying Japanese quails was supplemented either with retinyl acetate (RA) (50 x 10(3) IU/kg, group A), ascorbic acid (500 mg/kg, group C), or with both substances in combination with each other (group AC) and with tocopheryl acetate (37.8 IU/kg; groups AE and ACE). On days 1, 8, 14, 20 and 28, some quantitative parameters of eggs (mass of egg-shell, albumen and egg yolk, retinoid content of egg yolk) were measured. The egg production parameters were not significantly affected by the supplementations. By the end of the second week, the total vitamin A (retinyl esters + retinol) concentrations of the egg yolk were significantly higher in the groups receiving supplemented feed (AC, AE and AEC) than in the control group. Two weeks later (on day 28), the vitamin A levels were elevated significantly in all groups except the group treated with ascorbic acid. From the point of view of vitamin A fortification of the egg yolk, the combined supplementations (groups AC, AE, AEC) seem to be more effective. The results indicate that vitamin A content of the egg yolk can be increased by a short-term RA supplementation of the laying ration. The retinoids present in the natural substances of eggs could possibly be a good source of vitamin A for humans. PMID:8908745

Unimolecular decomposition rates for acetyl radical following the photodissociation of acetyl cyanide and aceticacid near 193 nm have been studied using ultrafast mass-resolved photoionization spectroscopy. In both cases, the parent decays with an instrumentally limited lifetime, while the acetyl radical behaves in a manner consistent with an RRKM mechanism, in contrast to our previous results on acetone. It is necessary to convolute the population distribution with the microcanonical RRKM rates in order to achieve this agreement. We have also undertaken an ab initio study of the excited states of acetyl cyanide to clarify the assignments of these states. The state excited at 193 nm arises from a ???* transition with a calculated transition velocity dipole moment oriented at an angle of 57° with respect to the C-C?N bond, resulting in an anisotropy parameter of -0.22. This is in reasonable agreement with the previous data of North et al. [J. Phys. Chem. A 101, 9224 (1997)]. The apparent RRKM behavior of the acetyl radical formed by the photodissociation of aceticacid and acetyl cyanide indicates that acetyl radical produced by the photodissociation of acetone at 193 nm may exhibit "extrinsic non-RRKM" effects, i.e., dynamic bottlenecks or mode specific effects.

Via N-acylhomoserine lactones, the GinI/GinR quorum-sensing system in Gluconacetobacter intermedius NCI1051, a gram-negative aceticacid bacterium, represses aceticacid and gluconic acid fermentation. Two-dimensional polyacrylamide gel electrophoretic analysis of protein profiles of strain NCI1051 and ginI and ginR mutants identified a protein that was produced in response to the GinI/GinR regulatory system. Cloning and nucleotide sequencing of the gene encoding this protein revealed that it encoded an OmpA family protein, named GmpA. gmpA was a member of the gene cluster containing three adjacent homologous genes, gmpA to gmpC, the organization of which appeared to be unique to vinegar producers, including “Gluconacetobacter polyoxogenes.” In addition, GmpA was unique among the OmpA family proteins in that its N-terminal membrane domain forming eight antiparallel transmembrane ?-strands contained an extra sequence in one of the surface-exposed loops. Transcriptional analysis showed that only gmpA of the three adjacent gmp genes was activated by the GinI/GinR quorum-sensing system. However, gmpA was not controlled directly by GinR but was controlled by an 89-amino-acid protein, GinA, a target of this quorum-sensing system. A gmpA mutant grew more rapidly in the presence of 2% (vol/vol) ethanol and accumulated aceticacid and gluconic acid in greater final yields than strain NCI1051. Thus, GmpA plays a role in repressing oxidative fermentation, including aceticacid fermentation, which is unique to aceticacid bacteria and allows ATP synthesis via ethanol oxidation. Consistent with the involvement of gmpA in oxidative fermentation, its transcription was also enhanced by ethanol and aceticacid. PMID:18487322

Many previous works have demonstrated that acetylcholinesterase (AChE) was enantioselectively inhibited by chiral organophosphorus insecticides (OPs) and that a significant difference in reactivation existed for AChE inactivated by (1R)- versus (1S,3S)-stereoisomers of isomalathion. It had been known that ?-naphthyl acetate esterase (ANAE), an enzyme which might play an essential role in the growth of plants and the defense of plants against environmental stress by regulating the concentration of hormones in plants, can be inhibited by OPs. However, it was unknown whether interaction of ANAE with chiral OPs was enantioselective. The present work investigated the inhibition kinetics and spontaneous reactivation of ANAE inactivated by enantiomers of malaoxon, isomalathion, and methamidophos. The order of inhibition potency is (R) > (S) for malaoxon, (1R,3R) > (1R,3S) > (1S,3R) > (1S,3S) for isomalathion, and (S) > (R) for methamidophos according to bimolecular rate constants of inhibition (ki), which is consistent with the order observed in the enantioselective inhibition of AChE by malaoxon, isomalathion, and methamidophos. The difference in spontaneous reactivation of AChE inactivated between (1R)- and (1S,3S)-isomers of isomalathion is conserved for ANAE. The observations indicated ANAE and AChE have similar selective inhibition kinetics and postinhibitory reactions in reaction with chiral OPs. PMID:24475784

In mammals, extended periods of fasting leads to the accumulation of blood ketone bodies including acetoacetate. Here we show that similar to the conversion of leucine to acetoacetate in fasting mammals, starvation conditions induced ketone body-like aceticacid generation from leucine in S. cerevisiae. Whereas wild-type and ras2? cells accumulated aceticacid, long-lived tor1? and sch9? mutants rapidly depleted it through a mitochondrial acetate CoA transferase-dependent mechanism, which was essential for lifespan extension. The sch9?-dependent utilization of aceticacid also required coenzyme Q biosynthetic genes and promoted the accumulation of intracellular trehalose. These results indicate that Tor-Sch9 deficiency extends longevity by switching cells to an alternative metabolic mode, in which aceticacid can be utilized for the storage of stress resistance carbon sources. These effects are reminiscent of those described for ketone bodies in fasting mammals and raise the possibility that the lifespan extension caused by Tor-S6K inhibition may also involve analogous metabolic changes in higher eukaryotes. PMID:24649827

In mammals, extended periods of fasting leads to the accumulation of blood ketone bodies including acetoacetate. Here we show that similar to the conversion of leucine to acetoacetate in fasting mammals, starvation conditions induced ketone body-like aceticacid generation from leucine in S. cerevisiae. Whereas wild-type and ras2? cells accumulated aceticacid, long-lived tor1? and sch9? mutants rapidly depleted it through a mitochondrial acetate CoA transferase-dependent mechanism, which was essential for lifespan extension. The sch9?-dependent utilization of aceticacid also required coenzyme Q biosynthetic genes and promoted the accumulation of intracellular trehalose. These results indicate that Tor-Sch9 deficiency extends longevity by switching cells to an alternative metabolic mode, in which aceticacid can be utilized for the storage of stress resistance carbon sources. These effects are reminiscent of those described for ketone bodies in fasting mammals and raise the possibility that the lifespan extension caused by Tor-S6K inhibition may also involve analogous metabolic changes in higher eukaryotes. PMID:24649827

Ring-opening reactions of semicyclic N,O-acetals possessing an exocyclic nitrogen atom with silicon-based nucleophiles (silyl enol ethers, ketene silyl acetals, allylic silanes, and trimethylsilyl cyanide) were systematically studied for the first time. It was found that the reactions were effectively catalyzed by a Lewis acid, trimethylsilyl trifluoromethanesulfonate (TMSOTf), to afford 1,4- and 1,5-amino alcohols in high yields. In reactions of 3-oxygen functionalized semicyclic N,O-acetals, high 1,2-syn-diastereoselectivity was obtained. By 1H NMR experiment, the formation of the O-trimethylsilylated ring-opened product was observed as the initial product. Furthermore, the epimerization between the diastereomers of a 3-benzyloxy semicyclic N,O-acetal suggested the transient formation of an acyclic iminium ion species as a reactive intermediate. It was also found that 3-acetoxy and 3-benzyloxy N,O-acetals showed a tendency for the larger nucleophile to provide higher syn-selectivity, while 3-tert-butyldiphenylsilyloxy N,O-acetals showed the opposite tendency. These stereochemical outcomes can be rationalized by assuming four transition state models for the acyclic iminium ion intermediate. The synthetic utility of the reaction has been demonstrated in the diastereoselective synthesis of piperidine alkaloids, (+)-isofebrifugine and (+/-)-sedacryptine. PMID:11741414

Antioxidant and immunomodulatory effects of anthocyanins are abundant in berberry fruits suggesting that they may have beneficial effects on inflammatory bowel diseases (IBD). The present study was carried out to investigate the anti-colitic effect of Berberis vulgaris fruit extract (BFE) compared to berberine chloride (BEC) and corticosteroids using an animal model of aceticacid induced experimental colitis. BFE with three different doses (375, 750, and 1500 mg/Kg) was administered orally or rectally prior to ulcer induction. BEC (10 mg/Kg), prednisolone (5 mg/Kg), hydrocortisone acetate enema (20 mg/Kg) and normal saline (5 mL/Kg) were considered as respective controls. The tissue was assessed macroscopically for damage scores, area, index and weight/length ratio. They were also examined histopathologically for inflammation extent and severity, crypt damage, invasion involvement and total colitis index. Results indicated that greater doses of oral BFE (750, 1500 mg/Kg) as well as BEC (10 mg/Kg) were effective to protect against colonic damage. By rectal pretreatment, the extract was only effective to diminish the ulcer index and the efficacy was not significant for mucosal inflammation parameters. In conclusion BFE, which is nearly devoid of berberine, was effective to protect against colitis and this might be attributed to its anthocyanin constituents. PMID:24363687

In anaerobic cultures of wild-type Saccharomyces cerevisiae, glycerol production is essential to reoxidize NADH produced in biosynthetic processes. Consequently, glycerol is a major by-product during anaerobic production of ethanol by S. cerevisiae, the single largest fermentation process in industrial biotechnology. The present study investigates the possibility of completely eliminating glycerol production by engineering S. cerevisiae such that it can reoxidize NADH by the reduction of aceticacid to ethanol via NADH-dependent reactions. Aceticacid is available at significant amounts in lignocellulosic hydrolysates of agricultural residues. Consistent with earlier studies, deletion of the two genes encoding NAD-dependent glycerol-3-phosphate dehydrogenase (GPD1 and GPD2) led to elimination of glycerol production and an inability to grow anaerobically. However, when the E. coli mhpF gene, encoding the acetylating NAD-dependent acetaldehyde dehydrogenase (EC 1.2.1.10; acetaldehyde + NAD+ + coenzyme A ? acetyl coenzyme A + NADH + H+), was expressed in the gpd1? gpd2? strain, anaerobic growth was restored by supplementation with 2.0 g liter?1 aceticacid. The stoichiometry of acetate consumption and growth was consistent with the complete replacement of glycerol formation by acetate reduction to ethanol as the mechanism for NADH reoxidation. This study provides a proof of principle for the potential of this metabolic engineering strategy to improve ethanol yields, eliminate glycerol production, and partially convert acetate, which is a well-known inhibitor of yeast performance in lignocellulosic hydrolysates, to ethanol. Further research should address the kinetic aspects of acetate reduction and the effect of the elimination of glycerol production on cellular robustness (e.g., osmotolerance). PMID:19915031

Polyurethanes are a unique class of biomaterials that are widely used in medical devices. In spite of their easy synthesis and excellent biocompatibility, polyurethanes are less explored for controlled drug delivery due to their slow or lack of degradation. In this paper, we report the design and development of novel acid degradable poly(acetal urethane) (PAU) and corresponding triblock copolymer micelles for pH-triggered intracellular delivery of a model lipophilic anticancer drug, doxorubicin (DOX). PAU with Mn ranging from 4.3 to 12.3 kg/mol was conveniently prepared from polycondensation reaction of lysine diisocyanate (LDI) and a novel diacetal-containing diol, terephthalilidene-bis(trimethylolethane) (TPABTME) using dibutyltin dilaurate (DBTDL) as a catalyst in N,N-dimethylformamide (DMF). The thiol-ene click reaction of Allyl-PAU-Allyl with thiolated PEG (Mn = 5.0 kg/mol) afforded PEG-PAU-PEG triblock copolymers that readily formed micelles with average sizes of about 90-120 nm in water. The dynamic light scattering (DLS) measurements revealed fast swelling and disruption of micelles under acidic pH. UV/vis spectroscopy corroborated that acetal degradation was accelerated at pH 4.0 and 5.0. The in vitro release studies showed that doxorubicin (DOX) was released in a controlled and pH-dependent manner, in which ca. 96%, 73%, and 30% of drug was released within 48 h at pH 4.0, 5.0, and 7.4, respectively. Notably, MTT assays displayed that DOX-loaded PEG-PAU-PEG micelles had a high in vitro antitumor activity in both RAW 264.7 and drug-resistant MCF-7/ADR cells. The confocal microscopy and flow cytometry experiments demonstrated that PEG-PAU-PEG micelles mediated efficient cytoplasmic delivery of DOX. Importantly, blank PEG-PAU-PEG micelles were shown to be nontoxic to RAW 264.7 and MCF-7/ADR cells even at a high concentration of 1.5 mg/mL. Hence, micelles based on poly(acetal urethane) have appeared as a new class of biocompatible and acid-degradable nanocarriers for efficient intracellular drug delivery. PMID:26110553

Solubility-diffusion theory, which treats the lipid bilayer membrane as a bulk lipid solvent into which permeants must partition and diffuse across, fails to account for the effects of lipid bilayer chain order on the permeability coefficient of any given permeant. This study addresses the scaling factor that must be applied to predictions from solubility-diffusion theory to correct for chain ordering. The effects of bilayer chemical composition, temperature, and phase structure on the permeability coefficient (Pm) of aceticacid were investigated in large unilamellar vesicles by a combined method of NMR line broadening and dynamic light scattering. Permeability values were obtained in distearoylphosphatidylcholine, dipalmitoylphosphatidylcholine, dimyristoylphosphatidylcholine, and dilauroylphosphatidylcholine bilayers, and their mixtures with cholesterol, at various temperatures both above and below the gel-->liquid-crystalline phase transition temperatures (Tm). A new scaling factor, the permeability decrement f, is introduced to account for the decrease in permeability coefficient from that predicted by solubility-diffusion theory owing to chain ordering in lipid bilayers. Values of f were obtained by division of the observed Pm by the permeability coefficient predicted from a bulk solubility-diffusion model. In liquid-crystalline phases, a strong correlation (r = 0.94) between f and the normalized surface density sigma was obtained: in f = 5.3 - 10.6 sigma. Activation energies (Ea) for the permeability of aceticacid decreased with decreasing phospholipid chain length and correlated with the sensitivity of chain ordering to temperature, [symbol: see text] sigma/[symbol: see text](1/T), as chain length was varied. Pm values decreased abruptly at temperatures below the main phase transition temperatures in pure dipalmitoylphosphatidylcholine and dimyristoylphosphatidylcholine bilayers (30-60-fold) and below the pretransition in dipalmitoylphosphatidylcholine bilayers (8-fold), and the linear relationship between in f and sigma established for liquid-crystalline bilayers was no longer followed. However, in both gel and liquid-crystalline phases in f was found to exhibit an inverse correlation with free surface area (in f = -0.31 - 29.1/af, where af is the average free area (in square angstroms) per lipid molecule). Thus, the lipid bilayer permeability of aceticacid can be predicted from the relevant chain-packing properties in the bilayer (free surface area), regardless of whether chain ordering is varied by changes in temperature, lipid chain length, cholesterol concentration, or bilayer phase structure, provided that temperature effects on permeant dehydration and diffusion and the chain-length effects on bilayer barrier thickness are properly taken into account. PMID:8994607

The transformation of the benzanilides 1 into 4-arylisochroman-3-aceticacids 8 applying the following sequence of reactions is described. At first, the 3-arylphthalides 3 were obtained via metallation [n-BuLi] of benzanilides 1 and subsequent treatment of the generated bis-lithiated anilides 2 with aromatic aldehydes. Next, the 3-arylphthalides 3 were reduced [LiBH4] to phthalanes 5 and then, via reductive metallation [Li\\/C10H8] and

The rhizome of Codonopsis lanceolata (family Campanulaceae), which contains lancemaside A as a main constituent, is frequently used in the traditional Chinese medicine for the treatment of inflammatory diseases. Lancemaside A exhibits anti-inflammatory effect in vitro and in vivo. However, orally administered lancemaside A is metabolized to echinocystic acid by the intestinal microflora and the metabolite is absorbed into the blood. Therefore, to understand whether echinocystic acid is effective against skin inflammatory diseases, we assessed its inhibitory effect against 12-O-tetra decanoylphorbol-13-acetate (TPA)-induced ear inflammation in mice. Topically administered echinocystic acid potently suppressed TPA-induced ear swelling. The suppression rates at 0.05 and 0.10 % concentrations were 65 and 73 %, respectively. Echinocystic acid also inhibited TPA-induced myeloperoxidase activity, as well as COX-2, iNOS, TNF-? and IL-1? expressions. Echinocystic acid inhibited NF-?B in TPA-treated mouse ears, as well as in lipopolysaccharide-stimulated peritoneal macrophages. Its potency is comparable with that of dexamethasone. These findings indicate that echinocystic acid may ameliorate inflammatory diseases, such as dermatitis. PMID:23515933

The New York State Energy Research and Development Authority (Energy Authority), Consolidated Edison Company of New York, Inc. (ConEd), the New York State Department of Transportation (NYSDOT), the New York State Thruway Authority (NYSTA), Chevron Chemical Company, the National Corn Growers Association (NCGA), and the Massachusetts Department of Public Works (MDPW) sponsored a research program to develop technology capable of producing Calcium Magnesium Acetate (CMA), an alternative road deicer, at a quality and cost which will allow its increased use. The objectives of this program were to determine the feasibility of: (1) producing CMA from regionally available waste and low grade organic feedstocks via biochemical engineering technologies; (2) operating the fermentation at concentrated product levels to reduce energy requirements and minimize drying process costs; (3) using this production approach to produce an environmentally acceptable CMA product; and (4) using and adapting an existing facility for a CMA commercial demonstration plant. The experimental program included:(1) selection of microorganisms for their ability to grow in the absence of sodium chloride and to tolerate high concentrations of calcium, magnesium, and acetate ions; (2) analysis of waste feedstocks for their potential conversion to acetate; (3) analysis of waste organic material for impurities in CMA that could carry over into the environment; (4) batch experiments to determine pH tolerance, growth in the absence of sodium chloride (NaCl), tolerance to magnesium, calcium and acetate ions, effect of substrate concentration, acid distribution, and acid production; and (5) semi-continuous laboratory scale anaerobic digestion experiments to determine loading rates, conversion efficiencies, and other design data. 67 refs., 33 figs., 66 tabs.

Indole-3-aceticacid (IAA) in highly purified extracts of rose achenes (Rosa rugosa var rubra) was quantified by means of ion-pair reversephase high performance liquid chromatography with spectrofluorimetric detection. Changes in IAA content were determined during a 14-week 4°C stratification, which leads to dormancy breakage, and during subsequent germination at 17°C. IAA was also determined in achenes stratified in parallel at 17°C, which does not induce release from dormancy. IAA decreased during the first 2 weeks of stratification both at 4°C and at 17°C. IAA remained low during the remaining 12 weeks of stratification at 4°C, whereas it continued to decrease in achenes kept at 17°C. An immediate increase in IAA during germination was followed by transients in the IAA level. The results suggest that IAA is without a regulating role in dormancy release although it seems to be involved in the germination process. PMID:16663829

Cervical cancer remains a significant cause of morbidity and mortality for women in developing countries, despite the fact that inexpensive, simple and effective screening methods are available. Visual inspection of the cervix with aceticacid (VIA) can be used as part of a "screen and treat" program to identify precancerous lesions for cryotherapy treatment. This case report details how the VIA screening test was incorporated into the care of a patient presenting to a maternal health clinic in Thomonde, Haiti which was staffed by doctors and medical students from Emory University School of Medicine in collaboration with Haiti Medishare. As demonstrated here, the VIA test requires minimal materials, can be efficiently incorporated into a physical exams, provides immediate results, and is easily demonstrated to and performed by local healthcare providers. The straightforward and sensitive VIA technique is an ideal cervical cancer screening method for resource poor areas. PMID:25464128

Cervical cancer remains a significant cause of morbidity and mortality for women in developing countries, despite the fact that inexpensive, simple and effective screening methods are available. Visual inspection of the cervix with aceticacid (VIA) can be used as part of a “screen and treat” program to identify precancerous lesions for cryotherapy treatment. This case report details how the VIA screening test was incorporated into the care of a patient presenting to a maternal health clinic in Thomonde, Haiti which was staffed by doctors and medical students from Emory University School of Medicine in collaboration with Haiti Medishare. As demonstrated here, the VIA test requires minimal materials, can be efficiently incorporated into a physical exams, provides immediate results, and is easily demonstrated to and performed by local healthcare providers. The straightforward and sensitive VIA technique is an ideal cervical cancer screening method for resource poor areas. PMID:25464128

A 62-old-year male presented to our hospital with induration of the prepuce and bleeding from the glans penis that occurred during sexual intercourse. Scrape cytology was performed, which showed class V, suspected squamous cell carcinoma. Computed tomography showed no metastases, and magnetic resonance imaging revealed no invasion of the corpus spongiosum. Circumcision and resection of the glanstumor were performed. Histopathological examination revealed squamous cell carcinoma in situ. We diagnosed the case as penile carcinoma in situ (pTisN0M0, UICC stage 0, and Jackson stage I). At 6 months postoperatively, local recurrence of penile carcinoma was detected by visual inspection after 5% aceticacid staining, and tumor resection was performed. At 9 months postoperatively (after the 2nd resection), the patient has remained disease-free, with no evidence of recurrence. PMID:25918268

The local irritating effect of Veen 3G Inj. (glucose-added aceticacid maintenance infusion solution) was examined in male rabbits. We studied the local irritating effect of the infusion solution compared with that of Ringer's solution, 5% sulfobromophthalein sodium injection, distilled water for injection or glucose-added Ringer's solution. In the vascular irritation test, macroscopical and histopathological changes induced by the infusion solution were not observed in the vessels. Moreover, in the hemolytic test, hemolysis of rabbit erythrocyte was not observed in the mixture with the infusion solution. In the present study, no change suggesting irritation by the infusion solution was observed in the in vivo vascular irritation test using the auricular vein of rabbits or in the in vitro hemolytic test using rabbit erythrocyte. In conclusion, in clinical use the infusion solution produces extremely slight adverse effects, such as vessel pain and phlebitis on the injection site. PMID:12073764

Background. Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of gastrointestinal tract of immune, genetic, and environmental origin. In the present study, we examined the effects of sesamol (SES), which is the active constituent of sesame oil in the aceticacid (AA) induced model for IBD in rats. Methods. The groups were divided into normal control, AA control, SES, and sulfasalazine (SS). On day 7, the rats were killed, colon was removed, and the macroscopic, biochemical, and histopathological evaluations were performed. Results. The levels of MPO, TBARS, and tissue nitrite increased significantly (P < 0.05) in the AA group whereas they reduced significantly in the SES and SS treated groups. Serum nitrite levels were found to be insignificant between the different groups. Conclusions. The mucosal protective effects of sesamol in IBD are due to its potential to reduce the myeloperoxidase and nitrite content. PMID:24616646

Recently, we showed that a combination of indole-3-aceticacid (IAA) and horseradish peroxidase (HRP) produces hydrogen peroxide (H2O2), and that this leads to the apoptosis of G361 human melanoma cells. In the present study, flow cytometric analysis confirmed that H2O2 is involved the IAA/HRP-induced apoptotic process. We also found that IAA/HRP increases cell surface CD95 (Fas/APO-1) expression, and that this is blocked by catalase treatment. Furthermore, blocking CD95 with a neutralizing antibody significantly restored IAA/HRP-induced apoptosis. In addition, the IAA/HRP-induced activations of CD95 downstream molecules, i.e., caspase-8, Bid, and caspase-3, were also inhibited by catalase. Moreover, a caspase-8 inhibitor significantly blocked IAA/HRP-induced apoptosis. These results indicate that IAA/HRP-induced apoptosis involves a CD95-initiated death receptor signaling pathway initiated by hydrogen peroxide. PMID:16880616

Higher alcohols and acetate esters are important flavour and aroma components in the food industry. In alcoholic beverages these compounds are produced by yeast during fermentation. Although Saccharomyces cerevisiae is one of the most extensively used species, other species of the Saccharomyces genus have become common in fermentation processes. This study analyses and compares the production of higher alcohols and acetate esters from their amino acidic precursors in three Saccharomyces species: Saccharomyces kudriavzevii, Saccharomyces uvarum and S. cerevisiae. The global volatile compound analysis revealed that S. kudriavzevii produced large amounts of higher alcohols, whereas S. uvarum excelled in the production of acetate esters. Particularly from phenylalanine, S. uvarum produced the largest amounts of 2-phenylethyl acetate, while S. kudriavzevii obtained the greatest 2-phenylethanol formation from this precursor. The present data indicate differences in the amino acid metabolism and subsequent production of flavour-active higher alcohols and acetate esters among the closely related Saccharomyces species. This knowledge will prove useful for developing new enhanced processes in fragrance, flavour, and food industries. PMID:25886016

Carbon-14 (C-14, t{sub 1/2} = 5.73x10{sup 3} yrs) from radioactive waste is one of the most important radioactive nuclides for environmental assessment in the context of geological disposal, and understanding the transfer of radioactive elements to plants is essential for public health safety. In order to obtain fundamental knowledge, culture experiments using marigold (Tagetes patula L.), tall fescue (Festuca arundinacea S.), paddy rice (Oryza sativa L.), radish (Raphanus sativus L.), and carrot (Daucus carota L.) plants were conducted to examine root-uptake and dynamics of C-14 in the laboratory. The C-14 radioactivity in each plant part (e.g. shoot, root, edible part, etc.), medium (e.g. culture solution, sand, etc.), and air was determined. The distribution of C-14 in the plants was visualized using autoradiography. For a comparison, autoradiography was also done using Na-22. Results of the present study indicated that C-14 labeled CO{sub 2} gas was released from the culture solution to the atmosphere. Clear autoradiography images were observed in plants for the shoots and lower roots which were soaked in the culture solution. The upper roots which were not soaked in the culture solution were not clearly imaged. In the radiotracer experiment using Na-22, a clear image was observed for the whole carrot seedling, even including the upper root, on the autoradiography. However, the amounts of C-14 aceticacid absorbed by all the plants through their roots were considered to be very small. Inorganic carbon transformed from C-14 aceticacid would be taken up by plants through the roots, and some fraction of C-14 would be assimilated into the shoots by photosynthesis. (authors)

Objective: Anti-inflammatory, immuno-modulatory, and antioxidant properties of Moringa oleifera Lam. suggest that it might have beneficial effects on colitis. The present study was performed to investigate the anticolitis effect of Moringa oleifera seeds hydro-alcoholic extract (MSHE) and its chloroform fraction (MCF) on aceticacid-induced colitis in rats. Materials and Methods: Both MSHE and MCF with three increasing doses (50, 100, and 200 mg/kg) were administered orally to separate groups of male Wistar rats, 2 h before ulcer induction (using aceticacid 4%) and continued for 5 days. Prednisolone (4 mg/kg) and normal saline (1 ml/kg) were used in reference and control groups, respectively. All rats were sacrificed 24 h after the last dose (at day 6) and tissue injuries were assessed macroscopically and pathologically. Results: Extracts with three doses mentioned before were effective to reduce weight of distal colon (8 cm) as a marker for inflammation and tissue edema. Three doses of MSHE and two greater doses of MCF (100 and 200 mg/kg) were effective to reduce ulcer severity, area, and index as well as mucosal inflammation severity and extent, crypt damage, invasion involvement, total colitis index, and MPO activity compared with controls. MCF (50 mg/kg) was not significantly effective in reducing evaluated parameters of colitis compared with controls. Conclusion: It is concluded that MSHE and MCF were both effective to treat experimental colitis and this might be attributed to their similar major components, biophenols and flavonoids. Since the efficacy was evident even in low doses of MSHE, presence of active constituents with high potency in seeds is persuasive. PMID:25050310

The hydrolysis of lignocellulosic biomass liberates sugars, primarily glucose and xylose, which are subsequently converted to ethanol by microbial fermentation. The rapid and efficient fermentation of xylose by recombinant Saccharomyces cerevisiae strains is limited by weak acids generated during biomass pretreatment processes. In particular, aceticacid negatively affects cell growth, xylose fermentation rate, and ethanol production. The ability of S. cerevisiae to efficiently utilize xylose in the presence of aceticacid is an essential requirement for the cost-effective production of ethanol from lignocellulosic hydrolysates. Here, an aceticacid-responsive transcriptional activator, HAA1, was overexpressed in a recombinant xylose-fermenting S. cerevisiae strain to yield BY4741X/HAA1. This strain exhibited improved cell growth and ethanol production from xylose under aerobic and oxygen limited conditions, respectively, in the presence of aceticacid. The HAA1p regulon enhanced transcript levels in BY4741X/HAA1. The disruption of PHO13, a p-nitrophenylphosphatase gene, in BY4741X/HAA1 led to further improvement in both yeast growth and the ability to ferment xylose, indicating that HAA1 overexpression and PHO13 deletion act by different mechanisms to enhance ethanol production. PMID:25282639

Miscibility studies on cellulose secondary acetate(CA)\\/Nylon 6(N6) blends have been carried out in this work. Dilute solution viscometry for the blend solutions using formic acid as the common solvent shows the existence of miscibility window.

Using a Beer-Lambert attenuation approach, we report measured total cross sections (TCSs) for positron scattering from vinyl acetate (C4H6O2) in the incident positron energy range 0.15-50 eV. In addition, we also report an independent atom model with screening corrected additivity rule computation results for the TCSs, differential and integral elastic cross sections, the positronium formation cross section and inelastic integral cross sections. The energy range of these calculations is 1-1000 eV. While there is a reasonable qualitative correspondence between measurement and calculation for the TCSs, in terms of the energy dependence of those cross sections, the theory was found to be a factor of ˜2 larger in magnitude at the lower energies, even after the measured data were corrected for the forward angle scattering effect.

In this study, influence of feedwater pH (2-12) was studied for hydrothermal carbonization (HTC) of wheat straw at 200 and 260°C. Aceticacid and KOH were used as acidic and basic medium, respectively. Hydrochars were characterized by elemental and fiber analyses, SEM, surface area, pore volume and size, and ATR-FTIR, while HTC process liquids were analyzed by HPLC and GC. Both hydrochar and HTC process liquid qualities vary with feedwater pH. At acidic pH, cellulose and elemental carbon increase in hydrochar, while hemicellulose and pseudo-lignin decrease. Hydrochars produced at pH 2 feedwater has 2.7 times larger surface area than that produced at pH 12. It also has the largest pore volume (1.1 × 10(-1) ml g(-1)) and pore size (20.2 nm). Organic acids were increasing, while sugars were decreasing in case of basic feedwater, however, phenolic compounds were present only at 260°C and their concentrations were increasing in basic feedwater. PMID:25710573

Viscosities of l-lysine monohydrochloride, l-histidine, and l-arginine in 1 m (mol · kg-1) aqueous solutions of sodium acetate, potassium acetate, and calcium acetate salts has been determined at (303.15, 308.15, 313.15, 318.15, and 323.15) K. The Falkenhagen coefficient, A, and Jones-Dole coefficient, B, relative viscosity, and specific viscosity of the solutions have also been determined using the measured viscosities. The results are interpreted in terms of solute-solute and solute-solvent interactions occurring in the system under investigation and also discussed in terms of the structure-making/breaking ability of the solute in these salt solutions. The structure making/breaking abilities of the solutes in the studied systems are strongly influenced by temperature.

The mixed solvated salt 4-(2-chloro­dibenzo[b,f][1,4]oxazepin-11-yl)piperazin-1-ium acetate–aceticacid–cyclo­hexane (2/2/1), C17H17ClN3O+·C2H3O2 ?·C2H4O2·0.5C6H12, crystallizes with one mol­ecule of protonated amoxapine (AXPN), an acetate anion and a mol­ecule of aceticacid together with half a mol­ecule of cyclo­hexane. In the centrosymmetric crystal, both enanti­omers of the protonated AXPN mol­ecule stack alternatively along [001]. Acetate anions connect the AXPN cations through N—H?O hydrogen bonding in the [010] direction, creating a sheet lying parallel to (100). The aceticacid mol­ecules are linked to the acetate anions via O—H?O hydrogen bonds within the sheets. Within the sheets there are also a number of C—H?O hydrogen bonds present. The cyclo­hexane solvent mol­ecules occupy the space between the sheets. PMID:25878802

The possibility of applying diethylammonium diethyldithiocarbamate and butyl acetate for the extraction of copper, cadmium, lead and bismuth from molar solutions of orthophosphoric acid, and from solutions containing up to 55% pyrophosphoric acid and 20% tripolyphosphoric acid has been investigated. Some characteristics of the various diethylammonium diethyldithiocarbamate-butyl acetate-phosphoric acid systems are described. Suitable conditions have been found for flame atomic-absorption spectrometric determination of the ions extracted. This extraction/AAS approach has been used to determine copper, cadmium, lead and bismuth in some iron-, aluminium- and tin-containing samples dissolved in concentrated orthophosphoric acid. The same approach is used for determining 10(-5)-10(-6)% copper, cadmium and lead in orthophosphoric acid and in alkali-metal mono and dihydrogen phosphates. PMID:18963249

Risk assessment for n-butyl acetate and metabolites n-butanol and n-butyric acid (the butyl series) can be accomplished with limited toxicity data and pharmacokinetic data for each compound through application of the "family approach" (Barton et al., 2000). The necessary quantita...

Ethyl esters of (9-subtituted-imidazo[1,2-a]benzimidazolyl-2)aceticacids were synthesized. The chemical properties of these esters (hydrolysis, decarboxylation, hydrazinolysis) and biological activity (fungicidal, antimicrobial, antiarrhythmic activity, and also affects on the brain rhythmogenesis) of the prepared compounds were studied. PMID:22497083

Ethylene diamine tetra-aceticacid (EDTA) and other chelates are widely employed in the electroless copper plating solutions and related chemistries used in printed circuit board (PCB) manufacturing. EDTA in particular, imparts many benefits to these processes but it is also becoming increasingly undesirable from an effluent treatment and environmental perspective. Consequently, there is a need to remove EDTA and similar

Electrochemical corrosion behavior of X65 steel in CO2-containing oilfield formation water in the presence of aceticacid (HAc) was investigated by various electrochemical measurements and analyses as well as thermodynamic calculations of ionic concentrations, reaction rate constants and equilibrium electrode potentials. A conceptual model was developed to illustrate corrosion processes of steel in oilfield formation water system. The anodic reactions

The synergistic solvent extraction of samarium (III) with mixtures of sec-octylphenoxy aceticacid (CA12, H2A2) and bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex301, H2B2) in n-heptane has been investigated from chloride medium. The methods of slope analysis and constant mole are used for the determination of the reaction. Samarium (III) is extracted with the mixture as SmH2Cl2AB2 instead of SmA3·HA or SmB3·HB when

A simple procedure was developed for the partial purification of plant tissue samples to be analyzed simultaneously for indole-3-aceticacid (IAA) and abscisic acid (ABA). The procedure relies on removal of contaminants by filtration through nylon and partitioning into dichloromethane. This procedure successfully purified both IAA and ABA from muskmelon, cotton, and broccoli tissue. Twenty individual samples can be purified and methylated in 8 h for analysis of free IAA and ABA with gas chromatography-selected ion monitoring-mass spectrometry. The use of microfiltration of aqueous samples through nylon offers new opportunities for improving the efficiency of existing sample purification procedures. PMID:16666735

The extraction of rare earth elements from chloride medium by mixtures of sec-nonylphenoxy aceticacid (CA100) with bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex301) or bis(2,4,4-trimethylpentyl) monothiophosphinic acid (Cyanex302) in n-heptane has been studied. The synergistic enhancement of the extraction of lanthanum (III) by mixtures of CA100 with Cyanex301 has been investigated using the methods of slope analysis and constant mole. The extracted

The Ghanaian cocoa bean heap fermentation process was studied through a multiphasic approach, encompassing both microbiological and metabolite target analyses. A culture-dependent (plating and incubation, followed by repetitive-sequence-based PCR analyses of picked-up colonies) and culture-independent (denaturing gradient gel electrophoresis [DGGE] of 16S rRNA gene amplicons, PCR-DGGE) approach revealed a limited biodiversity and targeted population dynamics of both lactic acid bacteria (LAB) and aceticacid bacteria (AAB) during fermentation. Four main clusters were identified among the LAB isolated: Lactobacillus plantarum, Lactobacillus fermentum, Leuconostoc pseudomesenteroides, and Enterococcus casseliflavus. Other taxa encompassed, for instance, Weissella. Only four clusters were found among the AAB identified: Acetobacter pasteurianus, Acetobacter syzygii-like bacteria, and two small clusters of Acetobacter tropicalis-like bacteria. Particular strains of L. plantarum, L. fermentum, and A. pasteurianus, originating from the environment, were well adapted to the environmental conditions prevailing during Ghanaian cocoa bean heap fermentation and apparently played a significant role in the cocoa bean fermentation process. Yeasts produced ethanol from sugars, and LAB produced lactic acid, aceticacid, ethanol, and mannitol from sugars and/or citrate. Whereas L. plantarum strains were abundant in the beginning of the fermentation, L. fermentum strains converted fructose into mannitol upon prolonged fermentation. A. pasteurianus grew on ethanol, mannitol, and lactate and converted ethanol into aceticacid. A newly proposed Weissella sp., referred to as “Weissella ghanaensis,” was detected through PCR-DGGE analysis in some of the fermentations and was only occasionally picked up through culture-based isolation. Two new species of Acetobacter were found as well, namely, the species tentatively named “Acetobacter senegalensis” (A. tropicalis-like) and “Acetobacter ghanaensis” (A. syzygii-like). PMID:17277227

The combination of indole-3-aceticacid (IAA) and horseradish peroxidase (HRP) has recently been proposed as a novel cancer therapy. However, the mechanism underlying the cytotoxic effect involved is substantially unknown. Here, we show that IAA/HRP treatment induces apoptosis in G361 human melanoma cells, whereas IAA or HRP alone have no effect. It is known that IAA produces free radicals when oxidized by HRP. Because oxidative stress could induce apoptosis, we measured the production of free radicals at varying concentrations of IAA and HRP. Our results show that IAA/HRP produces free radicals in a dose-dependent manner, which are suppressed by ascorbic acid or (-)-epigallocatechin gallate (EGCG). Furthermore, antioxidants prevent IAA/HRP-induced apoptosis, indicating that the IAA/HRP-produced free radicals play an important role in the apoptotic process. In addition, IAA/HRP was observed to activate p38 mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK), which are almost completely blocked by antioxidants. We further investigated the IAA/HRP-mediated apoptotic pathways, and found that IAA/HRP activates caspase-8 and caspase-9, leading to caspase-3 activation and poly(ADP-ribose) polymerase (PARP) cleavage. These events were also blocked by antioxidants, such as ascorbic acid or EGCG. Thus, we propose that IAA/HRP-induced free radicals lead to the apoptosis of human melanoma cells via both death receptor-mediated and mitochondrial apoptotic pathways. PMID:14607278

Spontaneous organic cocoa bean box fermentations were carried out on two different farms in Brazil. Physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (LAB) and aceticacid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. The main end-products of the catabolism of the pulp substrates (glucose, fructose, and citric acid) by yeasts, LAB, and AAB were ethanol, lactic acid, mannitol, and/or aceticacid. Lactobacillus fermentum and Acetobacter pasteurianus were the predominating bacterial species of the fermentations as revealed through (GTG)(5)-PCR fingerprinting of isolates and PCR-DGGE of 16S rRNA gene PCR amplicons of DNA directly extracted from fermentation samples. Fructobacillus pseudoficulneus, Lactobacillus plantarum, and Acetobacter senegalensis were among the prevailing species during the initial phase of the fermentations. Also, three novel LAB species were found. This study emphasized the possible participation of Enterobacteriaceae in the cocoa bean fermentation process. Tatumella ptyseos and Tatumella citrea were the prevailing enterobacterial species in the beginning of the fermentations as revealed by 16S rRNA gene-PCR-DGGE. Finally, it turned out that control over a restricted bacterial species diversity during fermentation through an ideal post-harvest handling of the cocoa beans will allow the production of high-quality cocoa and chocolates produced thereof, independent of the fermentation method or farm. PMID:21839382

The electronic spectroscopy of four different tryptophan analogs, 3-indole aceticacid, 3-indole propionic acid, tryptamine, and N-acetyltryptophan ethyl ester (NATE) has been studied in a supersonic molecular beam using laser-induced fluorescence and resonantly enhanced two-photon ionization. The electronic transition to the lowest excited singlet state occurs at 35 039, 34 965, 34 918, and 34 881±2 cm-1 for 3-indole aceticacid, 3-propionic acid, tryptamine, and NATE, respectively. The relatively small differences in the electronic origin transition frequencies suggests that the lowest excited singlet state for all of these moelcules is the 1Lb state. The spectra reveal that each of these molecules have stable conformers in the gas phase, analogous to our previously reported studies of tryptophan. A low frequency vibrational mode has been observed in 3-indole propionic acid, tryptamine, NATE, and tryptophan which involves motion of the side chain against the indole ring. We have observed that forming a van der Waals complex between tryptamine and a single methanol molecule causes the spectral features due to different conformers of the free molecule to collapse to a single line, suggesting that one particular conformer becomes the most stable species. This emphasizes the importance of including solvent interactions in any attempt to model the behavior of these molecules in solution.

Studies using inhibitors of indole-3-aceticacid (IAA) transport, not only for efflux but influx carriers, provide many aspects of auxin physiology in plants. 1-Naphtoxyacetic acid (1-NOA), an analog of the synthetic auxin 1-N-naphtalene aceticacid (NAA), inhibits the IAA influx carrier AUX1. However, 1-NOA also shows auxin activity because of its structural similarity to NAA. In this study, we have identified another candidate inhibitor of the IAA influx carrier. The compound, "7-B3; ethyl 2-[(2-chloro-4-nitrophenyl)thio]acetate," is a 2,4-dichlorophenoxyacetic acid (2,4-D) analog. At high concentrations (> 300 µM), 7-B3 slightly reduced IAA transport and tropic curvature of maize coleoptiles, whereas lower concentrations had almost no effect. We have analyzed the effects of 7-B3 on Arabidopsis thaliana seedlings. 7-B3 rescued the 2,4-D-inhibited root elongation, but not the NAA-inhibited root elongation. The effect of 7-B3 was weaker than that of 1-NOA. Both 1-NOA and 7-B3 inhibited DR5::GUS expression induced by IAA and 2,4-D, but not that induced by NAA. At high concentrations, 1-NOA exhibited auxin activity, but 7-B3 did not. Furthermore, 7-B3 inhibited apical hook formation in etiolated seedlings more effectively than did 1-NOA. These results indicate that 7-B3 is a potential inhibitor of IAA influx that has almost no effect on IAA efflux or auxin signaling. PMID:24800738

The virulence of Streptomyces scabiei, the causal agent of common scab, depends mainly on the production of the toxin thaxtomin A. S. scabiei also produces indole-3-aceticacid (IAA) but the role of this hormone in the interaction between pathogenic streptomycetes and plants has not yet been elucidated. Tryptophan is a biosynthetic precursor of both IAA and thaxtomin A. In this study, the effect of tryptophan on thaxtomin A and IAA production as well as its effect on the transcription of the corresponding biosynthetic genes in S. scabiei has been analyzed. In vitro IAA production depended on the availability of tryptophan. However, addition of this amino acid to the culture medium inhibited the biosynthesis of thaxtomin A. Expression of thaxtomin A biosynthetic genes nos and txtA were strongly repressed in the presence of tryptophan; however, modulation of the expression was not observed for the IAA biosynthetic genes iaaM and iaaH. The effects of an exogenous tryptophan supply on S. scabiei virulence were assessed on radish seedlings. Addition of tryptophan reduced symptoms on inoculated radish roots compared with seedlings grown in the absence of the bacterium, by way of inhibition of thaxtomin A production and increase of IAA biosynthesis. PMID:21521002

Pseudomonas fluorescens is an important biological component of agricultural soils that bestows a number of direct and indirect beneficial attributes to the plants. We analyzed the biocontrol strain P. fluorescens Psd for indole-3-aceticacid (IAA) biosynthesis and studied the effect of its consequent manipulation on its plant-growth-promoting (PGP) potential. While the indole pyruvic acid (IPyA) pathway commonly associated with PGP bacteria was lacking, the indole acetamide (IAM) pathway generally observed in phytopathogens was expressed in strain Psd. Overexpression of IAM pathway genes iaaM-iaaH, from Pseudomonas syringae subsp. savastanoi drastically increased IAA levels and showed a detrimental effect on sorghum root development. On the other hand, heterologous expression of the indole-3-pyruvate decarboxylase/phenylpyruvate decarboxylase gene (ipdC/ppdC) of the IPyA pathway from the PGP bacterium Azospirillum brasilense SM led to enhancement of the IAA level. A more favorable effect of this recombinant strain on sorghum root growth and development suggests that metabolic engineering could be used to generate strains with improved PGP function. PMID:21397014

Indole-3-aceticacid (IAA) can be oxidized via two mechanisms: a conventional hydrogen-peroxide-dependent pathway, and one that is hydrogen-peroxide-independent and requires oxygen. It has been shown here for the first time that only plant peroxidases are able to catalyse the reaction of IAA oxidation with molecular oxygen. Cytochrome c peroxidase (CcP), fungal peroxidases (manganese-dependent peroxidase, lignin peroxidase and Arthromyces ramosus peroxidase) and microperoxidase were essentially inactive towards IAA in the absence of added H2O2. An analysis of amino acid sequences allowed five structurally similar fragments to be identified in auxin-binding proteins and plant peroxidases. The corresponding fragments in CcP and fungal peroxidases showed no similarity with auxin-binding proteins. Five structurally similar fragments form a subdomain including the catalytic centre and two residues highly conserved among 'classical' plant peroxidases only, namely His-40 and Trp-117. The subdomain identified above with the two residues might be responsible for the oxidation of the physiological substrate of classical plant peroxidases, IAA. PMID:10359640

Conductive composite membrane-phytic acid (PA) doped polyaniline (PANI)/cellulose acetate (CA) (PANI-PA/CA) was prepared in a simple and environmental-friendly method, in which aniline was blended with CA/PA solution and polymerized before the phase conversion. The resultant composite membranes were characterized by SEM, EDX, FTIR-ATR, BET and electrical resistance measurements. When used as adsorbent for Hg(II) and Cr(VI) ions, the prepared composite membrane exhibits excellent adsorption capability. The adsorption of Hg(II) and Cr(VI) follows a pseudo-second-order kinetic model and best fits the Langmuir isotherm model, with the maximum adsorption capacity reaching 280.11 and 94.34 mg g(-1), respectively. The heavy metal loaded composite membrane can be regenerated and reused after treatment with acid or alkali solution, making it a promising and practical adsorbent for Hg(II) and Cr(VI) removal. Tests with river water were also carried out, indicating good performance and application. PMID:25127386

Despite the widespread availability of highly effective methods of contraception, unintended pregnancy is common. Unplanned pregnancies have been linked to a range of health, social and economic consequences. Emergency contraception reduces risk of pregnancy after unprotected intercourse, and represents an opportunity to decrease number of unplanned pregnancies and abortions. Emergency contraception pills (ECP) prevent pregnancy by delaying or inhibiting ovulation, without interfering with post fertilization events. If pregnancy has already occurred, ECPs will not be effective, therefore ECPs are not abortificants. Ulipristal acetate (17alpha-acetoxy-11beta-(4N-N,N-dymethilaminophenyl)-19-norpregna--4,9-diene-3,20-dione) is the first drug that was specifically developed and licensed for use as an emergency contraceptive. It is an orally active, synthetic, selective progesterone modulator that acts by binding with high affinity to the human progesterone receptor where it has both antagonist and partial agonist effects. It is a new molecular entity and the first compound in a new pharmacological class defined by the pristal stem. Up on the superior clinical efficacy evidence, UPA has been quickly recognized as the most effective emergency contraceptive pill, and recently recommended as the first prescription choice for all women regardless of the age and timing after intercourse. This article provides literature review of UPA and its role in emergency contraception. PMID:24851646

...acid at this time. However, the Endocrine Disruption Screening Program...acid, no adverse effects to the endocrine system are known or expected. Overall, the lack of evidence of endocrine disruption is consistent...

In the present study, sec-nonylphenoxy aceticacid (CA100) and its mixtures with four neutral organophosphorus extractants, tri-butyl-phosphate (TBP),\\u000a 2-ethylhexyl phosphonic acid di-2-ethyl ester (DEHEHP), Cyanex923, and Cyanex925 have been applied to the extraction of rare\\u000a earths. Results show that all the four mixing systems do not have evident synergistic effects on the extraction of rare earths.\\u000a The different extraction effects

We investigated changes in pain behavior after injection of aceticacid in the hindpaws of rats with L5 spinal nerve ligation (SNL)-induced neuropathy. We also examined immunoreactivity for acid-sensing ion channel 3 (ASIC3) in the dorsal root ganglion (DRG) of rats with L5 SNL. Two weeks after SNL, the withdrawal threshold to a mechanical stimulus was significantly lower in the

Electron transfer from K atoms to oriented aceticacid molecules produces acetate ions (and K{sup +}) when the CO{sub 2}H end of the molecule is attacked. The electron enters the {pi}{sub CO}* orbital and the donor atom distorts the molecule to allow migration to the {sigma}{sub OH}{sup *} orbital, thereby breaking the bond.

Gluconacetobacter diazotrophicus is an endophyte of sugarcane frequently found in plants grown in agricultural areas where nitrogen fertilizer input is low. Recent results from this laboratory, using mutant strains of G. diazotrophicus unable to fix nitrogen, suggested that there are two beneficial effects of G. diazotrophicus on sugarcane growth: one dependent and one not dependent on nitrogen fixation. A plant growth-promoting substance, such as indole-3-aceticacid (IAA), known to be produced by G. diazotrophicus, could be a nitrogen fixation-independent factor. One strain, MAd10, isolated by screening a library of Tn5 mutants, released only approximately 6% of the amount of IAA excreted by the parent strain in liquid culture. The mutation causing the IAA(-) phenotype was not linked to Tn5. A pLAFR3 cosmid clone that complemented the IAA deficiency was isolated. Sequence analysis of a complementing subclone indicated the presence of genes involved in cytochrome c biogenesis (ccm, for cytochrome c maturation). The G. diazotrophicus ccm operon was sequenced; the individual ccm gene products were 37 to 52% identical to ccm gene products of Escherichia coli and equivalent cyc genes of Bradyrhizobium japonicum. Although several ccm mutant phenotypes have been described in the literature, there are no reports of ccm gene products being involved in IAA production. Spectral analysis, heme-associated peroxidase activities, and respiratory activities of the cell membranes revealed that the ccm genes of G. diazotrophicus are involved in cytochrome c biogenesis. PMID:15292139

The bacterial aerobic respiratory chain has a terminal oxidase of the heme-copper oxidase superfamily, comprised of cytochrome c oxidase (COX) and ubiquinol oxidase (UOX); UOX evolved from COX. Acetobacter pasteurianus, an ?-Proteobacterial aceticacid bacterium (AAB), produces UOX but not COX, although it has a partial COX gene cluster, ctaBD and ctaA, in addition to the UOX operon cyaBACD. We expressed ctaB and ctaA genes of A. pasteurianus in Escherichia coli and demonstrated their function as heme O and heme A synthases. We also found that the absence of ctaD function is likely due to accumulated mutations. These COX genes are closely related to other ?-Proteobacterial COX proteins. However, the UOX operons of AAB are closely related to those of the ?/?-Proteobacteria (?-type UOX), distinct from the ?/?-Proteobacterial proteins (?-type UOX), but different from the other ?-type UOX proteins by the absence of the cyoE heme O synthase. Thus, we suggest that A. pasteurianus has a functional ?-type UOX but has lost the COX genes, with the exception of ctaB and ctaA, which supply the heme O and A moieties for UOX. Our results suggest that, in AAB, COX was replaced by ?/?-Proteobacterial UOX via horizontal gene transfer, while the COX genes, except for the heme O/A synthase genes, were lost. PMID:24862920

In order to find a way to induce rooting on cuttings of Hemarthria compressa cv. Ya’an under controlled conditions, a project was carried out to study the effect of naphthalene aceticacid (NAA) on rooting in stem cuttings and related physiological changes during the rooting process of Hemarthria compressa. The cuttings were treated with five concentrations of NAA (0, 100, 200 300, 400 mg/l) at three soaking durations (10, 20, 30 minutes), and cuttings without treatment were considered as control. Samples were planted immediately into pots after treatment. IAA-oxidase (IAAO) activity, peroxidase (POD) activity and polyphenol oxidase (PPO) activity were determined after planting. Results showed that NAA had positive effect on rooting at the concentration of 200 mg/l compared to other concentrations at 30 days after planting (DAP). Among the three soaking durations, 20 minutes (min) of 200 mg/l NAA resulted in higher percentages of rooting, larger numbers of adventitious roots and heavier root dry weight per cutting. The lowest IAAO activity was obtained when soaked at 200 mg/l NAA for 20 min soaking duration. This was consistent with the best rooting ability, indicating that the lower IAAO activity, the higher POD activity and PPO activity could be used as an indicator of better rooting ability for whip grass cuttings and might serve as a good marker for rooting ability in cuttings. PMID:24595064

Acinetobacter baumannii harbours a gene cluster similar to the iac locus of Pseudomonas putida 1290, which can catabolize the plant hormone indole 3-aceticacid (IAA) as an energy source. However, there has been no evidence showing that IAA can be utilized by A. baumannii. This study showed that A. baumannii can grow in M9 minimal medium containing IAA as the sole carbon source. A mutagenesis study indicated that iacA, encoded in the iac locus of A. baumannii, is involved in the catabolism of IAA. As shown by western blotting analysis, the IacA protein was detected in A. baumannii grown in M9 minimal medium with IAA but not with pyruvate, suggesting that the expression of iacA is regulated by the presence of IAA. In vitro studies have shown that IacA can oxidize indole, an IAA-like molecule, converting it to indoxyl, which spontaneously dimerises to form indigo. In this study, we show that the crude extracts from either wild-type A. baumannii or Escherichia coli overexpressing IacA can oxidize IAA. These results imply that the iac gene cluster of A. baumannii is involved in IAA degradation and that the iacA gene is upregulated when cells encounter IAA in their native environments. PMID:22311185

Development of a reliable in vitro plant regeneration procedure for hexaploid bread wheat (Triticum aestivum L.) is a prerequisite for its improvement by genetic transformation. Here, we report the effects of two growth regulators, benzyl adenine (BA) and indole aceticacid (IAA) on callus induction and plant regeneration from scutellum cultures of two commercial bread wheat cultivars: Giza 164 and Sakha 69. Callus induction was obtained from isolated embryos cultured on modified Murashige and Skoog (MS) basal medium. After four weeks of callus induction, all calli were plated on MS basal medium for regeneration. Wheat genotype and callus induction medium played a dominant role in plantlet regeneration. 2.0 mg/L BA and 0.2 mg/L IAA were the best combinations for inducing callus and let to highest regeneration frequency (81.67%) across the cultivars. Overall, based on our medium conditions, Giza 164 displayed higher regeneration frequency (81.11%) than Sakha 69. These results will facilitate genetic transformation for the economic varieties Giza 164 and Sakha 69. PMID:22538227

A major obstacle in the widespread application of microfiltration membranes in the wet separation processes such as wastewater treatment is the decline of permeates flux as a result of fouling. This study reports on the surface modification of cellulose acetate (CA) microfiltration membrane with amino acid L-3,4-dihydroxy-phenylalanine (L-DOPA) to improve fouling resistance of the membrane. The membrane surface was characterised using Fourier transform infrared spectroscopy (FTIR), water contact angle and zeta potential measurement. Porosity measurement showed a slight decrease in membrane porosity due to coating. Static adsorption experiments revealed an improved resistance of the modified membranes towards the adhesion of bovine serum albumin (BSA) as the model foulant. Dead end membrane filtration tests exhibited that the fouling resistance of the modified membranes was improved. However, the effect of the modification depended on the foulant solution concentration. It is concluded that L-DOPA modification is a convenient and non-destructive approach to enable low-BSA adhesion surface modification of CA microfiltration membranes. Nevertheless, the extent of fouling resistance improvement depends on the foulant concentration. PMID:23985522

Yeasts are widely distributed in nature and exist in association with other microorganisms as normal inhabitants of soil, vegetation, and aqueous environments. In this study, 12 yeast strains were enriched and isolated from leaf samples of the carnivorous plant Drosera indica L., which is currently threatened because of restricted habitats and use in herbal industries. According to similarities in large subunit and small subunit ribosomal RNA gene sequences, we identified 2 yeast species in 2 genera of the phylum Ascomycota, and 5 yeast species in 5 genera of the phylum Basidiomycota. All of the isolated yeasts produced indole-3-aceticacid (IAA) when cultivated in YPD broth supplemented with 0.1% L-tryptophan. Growth conditions, such as the pH and temperature of the medium, influenced yeast IAA production. Our results also suggested the existence of a tryptophan-independent IAA biosynthetic pathway. We evaluated the effects of various concentrations of exogenous IAA on yeast growth and observed that IAA produced by wild yeasts modifies auxin-inducible gene expression in Arabidopsis. Our data suggest that yeasts can promote plant growth and support ongoing prospecting of yeast strains for inclusion into biofertilizer for sustainable agriculture. PMID:25464336

Yeasts are widely distributed in nature and exist in association with other microorganisms as normal inhabitants of soil, vegetation, and aqueous environments. In this study, 12 yeast strains were enriched and isolated from leaf samples of the carnivorous plant Drosera indica L., which is currently threatened because of restricted habitats and use in herbal industries. According to similarities in large subunit and small subunit ribosomal RNA gene sequences, we identified 2 yeast species in 2 genera of the phylum Ascomycota, and 5 yeast species in 5 genera of the phylum Basidiomycota. All of the isolated yeasts produced indole-3-aceticacid (IAA) when cultivated in YPD broth supplemented with 0.1% L-tryptophan. Growth conditions, such as the pH and temperature of the medium, influenced yeast IAA production. Our results also suggested the existence of a tryptophan-independent IAA biosynthetic pathway. We evaluated the effects of various concentrations of exogenous IAA on yeast growth and observed that IAA produced by wild yeasts modifies auxin-inducible gene expression in Arabidopsis. Our data suggest that yeasts can promote plant growth and support ongoing prospecting of yeast strains for inclusion into biofertilizer for sustainable agriculture. PMID:25464336

2,4-dichlorophenoxyl aceticacid (2,4-D, pKa = 2.8) is used extensively as a herbicide in agricultural practices. Its sorption behavior on both untreated and soils treated to significantly remove specific components (organic and iron and manganese [Fe-Mn] oxides and hydroxides phases) was investigated under oxic and anoxic conditions. The chemical and structural heterogeneity of the soil components were characterized by elemental analysis and X-ray diffraction (XRD). The coexistence of the various components seems to either mask sorption sites on the untreated soil surfaces or inhibit interlayer diffusion of 2,4-D. All sorption data conform to the Freundlich description and a pseudo-second-order kinetic model. There was a strong positive correlation between sorption capacity Kd, and surface area (r(2) ? 0.704), but a negative correlation was uncovered with both pH and organic carbon (r(2) ? -0.860). The results indicate that 2,4-D is preferably sorbed under oxic rather than anoxic conditions and it is greater on soils containing a high Fe content. There was incomplete 2,4-D sorption reversibility, with desorption occurring more rapidly under anoxic conditions. The study suggests that stimulation of Fe III reduction could be used for the bioremediation of a 2,4-D-contaminated site. PMID:25996813

Background: Helichrysum oligocephalum DC. from Asteraceae family is an endemic plant growing wild in Iran. This study was carried out to investigate the effect of H. oligocephalum hydroalcoholic extract (HOHE) on ulcerative colitis (UC) induced by aceticacid (AA) in rats. Materials and Methods: Rats were grouped (n = 6) and fasted for 24 h before colitis induction. Treatments were started 2 h before the induction of colitis and continued for two consecutive days with different doses of HOHE (100, 200, and 400 mg/kg) orally (p.o.) and intraperitoneally (i.p.). The colon tissue was removed and tissue damages were scored after macroscopic and histopathologic assessments. Results: Among the examined doses of HOHE, 100 mg/kg was the most effective dose that reduced the extent of UC lesions and resulted in significant alleviation. Weight/length ratio as an index of tissue inflammation and extravasation was also diminished in the treatment group administered HOHE at a dose of 100 mg/kg, and the results showed correlation with macroscopic and histopathologic evaluations. These data suggest that HOHE (100 mg/kg) administered either p.o. or i.p. was effective in diminishing inflammation and ulcer indices in this murine model of acute colitis in a non–dose-related manner. Conclusions: H. oligocephalum could be considered as a suitable anticolitis alternative; however, further studies are needed to support this hypothesis for clinical setting. PMID:24761395

Epidemiological evidence has shown higher susceptibility of Children to the adverse effects of lead (Pb) exposure. However, experimental studies on Pb-induced neurotoxicity in prepubertal (PP) rats are limited. The present study aimed to examine the propensity of ferulic acid (FA), a commonly occurring phenolic acid in staple foods (fruits, vegetables, cereals, coffee etc.) to abrogate Pb-induced toxicity. Initially, we characterized Pb-induced adverse effects among PP rats exposed to Pb acetate (1,000-3,000 ppm in drinking water) for 5 weeks in terms of locomotor phenotype, activity of 5-aminolevulinic acid dehydratase (ALAD) in the blood, blood Pb levels and oxidative stress in brain regions. Further, the ameliorative effects of oral supplements of FA (25 mg/kg bw/day) were investigated in PP rats exposed to Pb (3,000 ppm). Pb intoxication increased the locomotor activity and FA supplements partially reversed the phenotype, while the reduced ALAD activity was also restored. FA significantly abrogated the enhanced oxidative stress in cerebellum (Cb) and hippocampus (Hc) as evidenced in terms of ROS generation, lipid peroxidation and protein carbonyls. Further, Pb-mediated perturbations in the glutathione levels and activity of enzymic antioxidants were also markedly restored. Furthermore, the protective effect of FA was discernible in striatum in terms of reduced oxidative stress, restored cholinergic activity and dopamine levels. Interestingly, reduced activity levels of mitochondrial complex I in Cb and enhanced levels in Hc among Pb-intoxicated rats were ameliorated by FA supplements. FA also decreased the number of damaged cells in cornu ammonis area CA1 and dentate gyrus as reflected by the histoarchitecture of Hc among Pb intoxicated rats. Collectively, our findings in the PP model allow us to hypothesize that ingestion of common phenolics such as FA may significantly alleviate the neurotoxic effects of Pb which may be largely attributed to its ability to abrogate oxidative stress. PMID:25322819

There is increasing evidence showing that low molecular weight organic acids (LMWOA) are involved in heavy metal resistance mechanisms in plants. The aim of this study was to investigate the effects of exogenous malic (MA) or acetic (AA) acids on the toxicity and accumulation of cadmium (Cd) in sunflower (Helianthus annuus L.). For this purpose, plants were grown in hydroponics under controlled conditions. Single Cd stress (5 ?M Cd for 14 days) induced strong phytotoxic effects, as indicated by a decrease in all growth parameters, concentration of photosynthetic pigments, and root activity, as well as a high level of hydrogen peroxide (H2O2) accumulation. Exogenous MA or AA (250 or 500 ?M) applied to the Cd-containing medium enhanced the accumulation of Cd by the roots and limited Cd translocation to the shoots. Moreover, the MA or AA applied more or less reduced Cd phytotoxicity by increasing the growth parameters, photosynthetic pigment concentrations, decreasing accumulation of H2O2, and improving the root activity. Of the studied organic acids, MA was much more efficient in mitigation of Cd toxicity than AA, probably by its antioxidant effects, which were stronger than those of AA. Plant response to Cd involved decreased production of endogenous LMWOA, probably as a consequence of severe Cd toxicity. The addition of MA or AA to the medium increased endogenous accumulation of LMWOA, especially in the roots, which could be beneficial for plant metabolism. These results imply that especially MA may be involved in the processes of Cd uptake, translocation, and tolerance in plants. PMID:26115548

Pregnant hamsters were given a single oral dose (35 µmol\\/kg) of all-trans-retinoic acid, 13-cis-retinoic acid, all-trans-4-oxo-retinoic acid, 9-cis-retinal or all-trans-retinyl acetate during the early primitive streak stage of development. The radioactivity associated with the acidic retinoids was distributed to all tissues sampled (including placenta and fetus), with the largest accumulation in the liver and the least accumulation in fat. Radioactivity

Bismuth titanate (Bi4Ti3O12) thin films were fabricated by a spin coating deposition and rapid thermal processing (RTP) technique. The acetate-derived solution for deposition was synthesized by blending dissolved bismuth acetate in aqueous aceticacid and then adding titanium acetate. A series of electrically insulating, semiconducting and conducting substrates were evaluated for Bi4Ti3O12 films deposition. X-ray diffraction indicated that the initial

Cellulose acetate is one of the components employed in drug controlled-release systems in the form of membranes. The aim of this study was to examine the controlled-release of doxycycline employing cellulose acetate symmetric and asymmetric membranes as matrices. The cellulose triacetate was produced from sugarcane bagasse through a homogeneous acetylation reaction, using aceticacid as the solvent, acetic anhydride as

Metabolic pathways play an indispensable role in supplying cellular systems with energy and molecular building blocks for growth, maintenance and repair and are tightly linked with lifespan and systems stability of cells. For optimal growth and survival cells rapidly adopt to environmental changes. Accumulation of aceticacid in stationary phase budding yeast cultures is considered to be a primary mechanism of chronological aging and induction of apoptosis in yeast, which has prompted us to investigate the dependence of aceticacid toxicity on extracellular conditions in a systematic manner. Using an automated computer controlled assay system, we investigated and model the dynamic interconnection of biomass yield- and growth rate-dependence on extracellular glucose concentration, pH conditions and aceticacid concentration. Our results show that toxic concentrations of aceticacid inhibit glucose consumption and reduce ethanol production. In absence of carbohydrates uptake, cells initiate synthesis of storage carbohydrates, trehalose and glycogen, and upregulate gluconeogenesis. Accumulation of trehalose and glycogen, and induction of gluconeogenesis depends on mitochondrial activity, investigated by depletion of the Hap2-3-4-5 complex. Analyzing the activity of glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), pyruvate kinase (PYK), and glucose-6-phosphate dehydrogenase (G6PDH) we found that while high aceticacid concentration increased their activity, lower aceticacids concentrations significantly inhibited these enzymes. With this study we determined growth and functional adjustment of metabolism to aceticacid accumulation in a complex range of extracellular conditions. Our results show that substantial acidification of the intracellular environment, resulting from accumulation of dissociated aceticacid in the cytosol, is required for aceticacid toxicity, which creates a state of energy deficiency and nutrient starvation. PMID:23050242

Nomegestrol acetate/estradiol is a combined oral contraceptive with approval in many countries. This fixed-dose combination tablet contains nomegestrol acetate, a highly selective progestogen, and estradiol, a natural estrogen. It is the first monophasic combined oral contraceptive to contain estradiol, and is taken in 28-day cycles, consisting of 24 active therapy days with 4 placebo days (i.e. 24/4-day cycles). In two large, 1-year, randomized, open-label, multicentre, phase III trials in healthy adult women (aged 18-50 years), nomegestrol acetate/estradiol was at least as effective as drospirenone/ethinylestradiol as contraceptive therapy, as the pregnancy rates in women aged 18-35 years (primary efficacy population) in terms of the Pearl Index (primary endpoint) were numerically lower with nomegestrol acetate/estradiol, although the between-group difference was not statistically significant. In both trials, nomegestrol acetate/estradiol was given in a 24/4-day cycle, and drospirenone/ethinylestradiol was given in a 21/7-day cycle. The criteria for using condoms in case of forgotten doses were less stringent in the nomegestrol acetate/estradiol group than in the drospirenone/ethinylestradiol group. Nomegestrol acetate/estradiol therapy for up to 1 year was generally well tolerated in healthy adult women, with an acceptable tolerability profile in line with that expected for a combined oral contraceptive. The most commonly reported adverse events were acne and abnormal withdrawal bleeding (most often shorter, lighter or absent periods). Overall, compared with drospirenone/ethinylestradiol, nomegestrol acetate/estradiol appeared to be associated with less favourable acne-related outcomes, and shorter, lighter or absent periods. PMID:22950535

Microbial enantioselective ester hydrolysis for the preparation of optically active (3R,5S)-(-)-5-phenyl-4,1-benzoxazepine-3-aceticacid derivatives as potent squalene synthase inhibitors was investigated. Pseudomonas diminuta and Pseudomonas taetrolens hydrolyzed the racemic ethyl ester of the 5-(2-chlorophenyl) analogue to yield the (-)-carboxylic acid with excellent enantiomeric excess (>99% ee). We found that the (-)-enantiomer was an active inhibitor. Bulkiness of the ester moiety did not affect the enantioselectivity but did affect reactivity. The racemic ethyl ester of the 5-(2-methoxyphenyl) analogue, 5-(2,3-dimethoxyphenyl) analogue and 5-(2,4-dimethoxyphenyl) analogue were also hydrolyzed with Pseudomonas taetrolens to afford enantiomerically pure (-)-carboxylic acids in large scale. As another route to (3R,5S)-(-)-7-chloro-5-(2,3-dimethoxyphenyl)-1-neopentyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-aceticacid [(-)-1c], the earlier intermediate (-)-2-amino-5-chloro-alpha-(2,3-dimethoxyphenyl)benzyl alcohol [(-)-12] was successfully obtained by asymmetric hydrolysis of (+/-)-5-chloro-alpha-(2,3-dimethoxyphenyl)-2-pivaloylaminobenzyl acetate with Pseudomonas sp. S-13 with >99% ee in kilogram scale followed by alkaline treatment. The product (-)-12 was converted to (-)-1c without racemization. PMID:11824586

The structure of the title tri­fluoro­aceticacid adduct, C17H12N2O3·C2HF3O2, contains a tri­fluoro­aceticacid mol­ecule hydrogen bonded to the imine N atom of the imidazole ring of a nearly planar four-fused-ring system (r.m.s. deviatiation = 0.013?Å). The carb­oxy­lic acid group of the triflouro­aceticacid mol­ecule is twisted with respect to the mean plane of the four-fused-ring sytem by 75.9?(2)°. A short intra­molecular C—H?O hydrogen bond occurs. In the crystal, the adduct mol­ecules are arranged into stacks along the b axis via ?–? inter­actions between imidazole rings and between imidazole and one of the benzene rings [centroid–centroid distances 3.352?(2) and 3.485?(2)?Å, respectively]. Molecules are linked via C—H?O hydrogen bonds, forming an alternating polymeric head-to-head/tail-to-tail stepped chain approximately along the a-axis direction and tilted on an axis bisecting the b and c axes. PMID:23795131

The comparative analysis of plant hormones was undertaken on a 1-naphthaleneacetic acid tolerant mutant and normal tobacco (Nicotiana tabacum cv Xanthi) plantlets. The mutant plantlet was scrubby and impaired in its root morphogenesis. Degeneration of the root meristem was studied on tissue sections; it appeared very fast (as early as the 3rd or 4th day after sowing), after which the root was further transformed into a callus. Indoleacetic acid (IAA), abscisic acid (ABA), and the isopentenyladenine (iP)- and trans-zeatin(Z)-type cytokinin levels were measured in terminal buds and root tips 13 days after sowing, by enzyme linked immunosorbent assay of high performance liquid chromatography fractions. Some differences appeared between the apical buds of the two genotypes, but the mutant tobacco differed from the wild type mainly by the presence of higher levels of IAA, ABA, and iP + isopentenyladenosine (iPA) in its small root. Thus, the IAA, ABA, and iP + iPA contents were increased by a factor of 15, 7, and 24 times, respectively, in mutant root compared to wild-type tobacco roots. Previous work has shown that the mutation impairs membrane polarization effects induced by auxin at the cell level. The present results would favor the hypothesis that the mutation has also affected the control of growth regulator accumulation in tissues. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:16666551

2,4-Dichlorophenoxy aceticacid dimethyl amine salt (2,4-D DMA), as one of the phenoxy acids, is used as a herbicide mainly against broad-leaf weeds in cereal crops, sugar cane, and on turf, pasture, and non-crop land. Some formulations of 2,4-D may be contaminated with dioxins. Recently, it has been shown that chlorinated organic compounds, dioxins, and furans are present in mother's milk and may cause developmental defects in children's teeth. Therefore, we aimed to evaluate the effects of 2,4-D DMA on odontogenesis in rats. 2,4-D DMA was given orally combined with rat food to pregnant albino rats. Each group consisted of two pregnant rats and, 0 (control, group A), 25 ppm (group B), 50 ppm (group C), and 100 ppm (group D) 2,4-D DMA was given to each pregnant rat as daily intake. 2,4-D DMA affected young rat's dental development and dose-related findings were found in experimental groups. The odontoblast layer was irregular and globular dentin formation was present in Groups B, C, and D but not in the control group. Thickness of enamel decreased in Groups C and D. The results of the study have shown that 2,4-D DMA could disturb dental development in rats even in relatively low doses. It is concluded that environmental contaminants such as chlorinated organic pesticides may play an important role in infant's dental development when taken via mother's milk. PMID:11341697

The oxidation of acetate to hydrogen, and the subsequent conversion of hydrogen and carbon dioxide to methane, has been regarded largely as a niche mechanism occurring at high temperatures or under inhibitory conditions. In this study, 13 anaerobic reactors and sediment from a temperate anaerobic lake were surveyed for their dominant methanogenic population by using fluorescent in situ hybridization and for the degree of acetate oxidation relative to aceticlastic conversion by using radiolabeled [2-14C]acetate in batch incubations. When Methanosaetaceae were not present, acetate oxidation was the dominant methanogenic pathway. Aceticlastic conversion was observed only in the presence of Methanosaetaceae. PMID:16820524

Oral acetate supplementation enhances glycogen synthesis in some mammals. However, while acetate is a significant energy source for skeletal muscle at rest in horses, its effects on glycogen resynthesis are unknown. We hypothesized that administration of an oral sodium acetate-aceticacid solution with a typical grain and hay meal after glycogen-depleting exercise would result in a rapid appearance of acetate in blood with rapid uptake by skeletal muscle. It was further hypothesized that acetate taken up by muscle would be converted to acetyl CoA (and acetylcarnitine), which would be metabolized to CO2 and water via the tricarboxylic acid cycle, generating ATP within the mitochondria and thereby allowing glucose taken up by muscle to be preferentially incorporated into glycogen. Gluteus medius biopsies and jugular venous blood were sampled from nine exercise-conditioned horses on two separate occasions, at rest and for 24 h following a competition exercise test (CET) designed to simulate the speed and endurance test of a 3 day event. After the CETs, horses were allowed water ad libitum and either 8 l of a hypertonic sodium acetate-aceticacid solution via nasogastric gavage followed by a typical hay-grain meal (acetate treatment) or a hay-grain meal alone (control treatment). The CET significantly decreased muscle glycogen concentration by 21 and 17% in the acetate and control treatments, respectively. Acetate supplementation resulted in a rapid and sustained increase in plasma [acetate]. Skeletal muscle [acetyl CoA] and [acetylcarnitine] were increased at 4 h of recovery in the acetate treatment, suggesting substantial tissue extraction of the supplemented acetate. Acetate supplementation also resulted in an enhanced rate of muscle glycogen resynthesis during the initial 4 h of the recovery period compared with the control treatment; however, by 24 h of recovery there was no difference in glycogen replenishment between trials. It is concluded that oral acetate could be an alternative energy source in the horse. PMID:19429643

Conductive poly(?-caprolactone) (PCL)+4% multiwalled carbon nanotubes (MWCNTs)\\/poly(lactic acid) (PLA)=50\\/50wt% blend multifilament fibres were melt-spun and a woven textile was made by a handloom with the conductive fibres in weft direction. The fibres were tested for cyclic liquid sensing in ethyl acetate and acetone as two moderate solvents and in ethanol as a poor solvent. The liquid sensing responses, namely the

The ecotoxicity and mobility of trace elements in soils are often evaluated through analytical results resulting from operationally-defined\\u000a determinations (single and sequential extractions), e.g. based on EDTA, aceticacid etc. extractions. The significance and\\u000a comparability of these results is highly dependent on the procedures used (standardized protocols or standards adopted by\\u000a international bodies) and their quality control relies on the

The extraction of rare earths with mixtures of sec-nonylphenoxy aceticacid (CA100, H2A2) and 1,10-phenanthroline (phen, B) in benzene has been investigated from nitrate medium. The mixtures show synergistic effects on all the selected rare earths, lanthanum, neodymium, samarium, terbium, ytterbium, and yttrium. The extraction stoichiometries of samarium and yttrium with CA100 and its mixtures with phen have been studied

Endogenous, free indol-3yl-aceticacid (IAA) levels were measured in the main stem in the 10-year-old cambial zone, in the adjoining differentiating xylem, and in the adjoining mature xylem of 15–20-year-old Pinus contorta Dougl. by single-ion-current monitoring, combined gas chromatography — mass spectrometry, on several dates from early spring to early winter. Microscopy was used to determine the state of cambial

A method and apparatus are disclosed for converting waste gases from industrial processes such as oil refining, carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various organic acids or alcohols by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified. In an exemplary recovery process, the bioreactor raffinate is passed through an extraction chamber into which one or more non-inhibitory solvents are simultaneously introduced to extract the product. Then, the product is separated from the solvent by distillation. Gas conversion rates can be maximized by use of centrifuges, hollow fiber membranes, or other means of ultrafiltration to return entrained anaerobic bacteria from the bioreactor raffinate to the bioreactor itself, thus insuring the highest possible cell concentration. 5 figs.

The anhydrous salts of 2-(1H-indol-3-yl)ethanamine (tryptamine) with isomeric (2,4-di-chloro-phen-oxy)aceticacid (2,4-D) and (3,5-di-chloro-phen-oxy)acetic (3,5-D), both C10H13N2 (+)·C8H5Cl2O3 (-) [(I) and (II), respectively], have been determined and their one-dimensional hydrogen-bonded polymeric structures are described. In the crystal of (I), the aminium H atoms are involved in three separate inter-species N-H?O hydrogen-bonding inter-actions, two with carboxyl-ate O-atom acceptors and the third in an asymmetric three-centre bidentate carboxyl-ate O,O' chelate [graph set R 1 (2)(4)]. The indole H atom forms an N-H?Ocarboxyl-ate hydrogen bond, extending the chain structure along the b-axis direction. In (II), two of the three aminium H atoms are also involved in N-H?Ocarboxyl-ate hydrogen bonds similar to (I) but with the third, a three-centre asymmetric inter-action with carboxyl-ate and phen-oxy O atoms is found [graph set R 1 (2)(5)]. The chain polymeric extension is also along b. There are no ?-? ring inter-actions in either of the structures. The aminium side-chain conformations differ significantly between the two structures, reflecting the conformational ambivalence of the tryptaminium cation, as found also in the benzoate salts. PMID:26090147

The anhydrous salts of 2-(1H-indol-3-yl)ethanamine (tryptamine) with isomeric (2,4-di­chloro­phen­oxy)aceticacid (2,4-D) and (3,5-di­chloro­phen­oxy)acetic (3,5-D), both C10H13N2 +·C8H5Cl2O3 ? [(I) and (II), respectively], have been determined and their one-dimensional hydrogen-bonded polymeric structures are described. In the crystal of (I), the aminium H atoms are involved in three separate inter-species N—H?O hydrogen-bonding inter­actions, two with carboxyl­ate O-atom acceptors and the third in an asymmetric three-centre bidentate carboxyl­ate O,O? chelate [graph set R 1 2(4)]. The indole H atom forms an N—H?Ocarboxyl­ate hydrogen bond, extending the chain structure along the b-axis direction. In (II), two of the three aminium H atoms are also involved in N—H?Ocarboxyl­ate hydrogen bonds similar to (I) but with the third, a three-centre asymmetric inter­action with carboxyl­ate and phen­oxy O atoms is found [graph set R 1 2(5)]. The chain polymeric extension is also along b. There are no ?–? ring inter­actions in either of the structures. The aminium side-chain conformations differ significantly between the two structures, reflecting the conformational ambivalence of the tryptaminium cation, as found also in the benzoate salts.

Objective: To find out whether DTPA-DG complex can enhance clearance of intracellular free iron. Materials and Methods: Diethylenetriaminepentaacetic acid-D-deoxy-glucosamine (DTPA-DG) was synthesized and examined for its activity as a cell-permeable iron chelator in human hepatocellular carcinoma (HEPG2) cell line exposed to high concentration of iron sulfate and compared with deferoxamine (DFO), a prototype iron chelator. The effect of DTPA-DG on cell viability was monitored using the 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide MTT assay as well. Results: There was a significant increase of iron level after iron overload induction in HEPG2 cell culture. DTPA-DG presented a remarkable capacity to iron burden reducing with estimated 50% inhibitory concentration value of 65.77 nM. In fact, glycosyl moiety was gained access of DTPA to intracellular iron deposits through glucose transporter systems. Conclusion: DTPA-DG, more potent than DFO to sequester deposits of free iron with no profound toxic effect. The results suggest the potential of DTPA-DG in chelating iron and permitting its excretion from primary organ storage. PMID:24554907

Non-selective cyclooxygenase (COX) inhibitors exert effects on lower urinary tract function in several species. The exact contributions of COX-1 and COX-2 isozymes have not been studied much. The present studies investigated the effects of non- and selective COX inhibitors on bladder irritation in the cat.Chloralose-anaesthetised female cats were catheterised through the bladder dome for cystometric evaluation of bladder responses to intravesical infusion of saline or aceticacid. Bladder capacity, voiding efficiency, threshold pressure, and reflex-evoked bladder contraction amplitude and duration were measured. The cat COX selectivity of the doses of inhibitors examined was determined using an in vitro whole-blood assay and analysis of plasma levels. Pretreatment with indomethacin or ketoprofen (non-selective COX inhibitors; 0.3 mg kg(-1) i.v.) inhibited aceticacid-evoked irritation (characterised by a decrease in bladder capacity in vehicle pretreated animals). FR-122047 (selective COX-1 inhibitor), NS-398 and nimesulide (selective COX-2 inhibitors; 1 and 3 mg kg(-1) i.v.) had no effects on bladder irritation. Analysis of plasma levels of the doses examined and determination of COX-1 and COX-2 inhibition in cat whole blood confirmed the reported selectivity of these compounds in this species. The present studies suggest that dual COX inhibition is required to attenuate aceticacid-evoked bladder irritation in the cat. PMID:16547526

Several methods are used to evaluate gastric motility in rodents, but they all have technical limitations. Recent technical developments enable a convenient method to evaluate gastric motility. The (13)C-aceticacid breath test in rodents is a non-invasive and repeatable method that can be used without physical restraints. The present study aimed to validate the (13)C-aceticacid breath test by measuring the effects of loperamide, morphine, mosapride, and itopride on gastric emptying in mice. Loperamide (1-10 mg/kg) and morphine (1.25-10 mg/kg) slowed gastric emptying and decreased the maximum concentration (C(max)) and area under the curve (AUC(90 min)) value in a dose-dependent manner. Mosapride (0.2-5 mg/kg) accelerated gastric emptying and increased C(max) value. Mosapride (20 mg/kg) did not accelerate gastric emptying on the (13)C-breath test. Itopride (30 mg/kg, per os) significantly accelerated gastric emptying compared with the vehicle group. In a comparison with the conventional phenol red test, there was a correlation between the C(max) value of breath test and gastric emptying (%) of phenol red tests in treatment with loperamide or mosapride. These results indicate that the (13)C-aceticacid breath test is an accurate, noninvasive, and simple method for monitoring gastric emptying in mice. This method is useful to assess the effect of drugs and gut function pharmacologically. PMID:18827355

In this investigation, chlorophenol (CP) containing industrial wastewater was remediated by ultraviolet irradiation in conjunction with organic oxidants, peroxy aceticacid (PAA); para nitro benzoic acid (PNBA); and methyl ethyl ketone peroxide (MEKP). CP mineralization was studied with regard to chemical oxygen demand (COD) and chloride ion release under identical test conditions. COD depletion to the extent of 81% by PAA, 66% by PNBA, and 67% by MEKP was noted along with an upwardly mobile trend of chloride ion release upon irradiation of samples at 254 nm. A 90-99% decrease in CP concentration (as per high pressure liquid chromatography (HPLC) analysis) was achieved with an additional 15.0 ml of organic oxidant in all cases. Gas chromatography high resolution mass spectroscopy (GC-HRMS) results also indicated the formation of such reaction products as are free from chlorine substitutions. This treatment also leads to total decolorization of the collected samples. PMID:24647192

Studies were conducted to assess glacial aceticacid (GAA) with various host plant volatiles (HPVs) and the sex pheromone, (E,E)-8, 10-dodecadien-1-ol, of codling moth, Cydia pomonella (L), as lures in traps for tortricid pests that often co-occur in tree fruits in the western United States. In addition to codling moth, field trapping studies were conducted with oriental fruit moth, Grapholita molesta (Busck), obliquebanded leafroller Choristoneura rosaceana (Harris), the leafroller Pandemis pyrusana Kearfott, and the eyespotted budmoth, Spilonota ocellana (Denis and Schiffermüller). HPVs included ethyl (E,Z)-2,4-decadienoate (pear ester), (E)-4,8-dimethyl-1,3,7-nonatriene, butyl hexanoate, (E)-?-ocimene, (E)-?-farnesene, and farnesol. Three types of GAA co-lures differing in a 10-fold range in weekly evaporation rates were tested. The evaporation rate of GAA co-lures was an important factor affecting moth catches. The highest rate tested captured fewer codling moth but more leafrollers and eyespotted budmoth. GAA co-lures caught both sexes of each species. The field life of butyl hexanoate and (E)-?-ocimene lures were much shorter than pear ester or sex pheromone lures. Adding GAA to pear ester or to (E)-?-ocimene significantly increased the catches of only codling moth or oriental fruit moth, respectively. Combining pear ester or (E)-?-ocimene with GAA did not affect the catch of either species compared with the single more attractive HPV. Adding HPVs to GAA did not increase the catches of either leafroller species or eyespotted budmoth. Traps baited with pear ester, sex pheromone, and GAA for monitoring codling moth were also effective in classifying pest pressure of both leafroller species within orchards. PMID:25268327

Erwinia herbicola pv. gypsophilae (Ehg), which induces galls on Gypsophila paniculata, harbors two major pathways for indole-3-aceticacid (IAA) synthesis, the indole-3-acetamide (IAM) and indole-3-pyruvate (IPyA) routes, as well as cytokinin biosynthetic genes. Mutants were generated in which the various biosynthetic routes were disrupted separately or jointly in order to assess the contribution of IAA of various origins and cytokinins to pathogenicity and epiphytic fitness. Inactivation of the IAM pathway or cytokinin biosynthesis caused the largest reduction in gall size. Inactivation of the IPyA pathway caused a minor, nonsignificant decrease in pathogenicity. No further reduction in gall size was observed by the simultaneous inactivation of both IAA pathways only or in combination with that of cytokinin production. However, inactivation of the IPyA pathway caused a 14-fold reduction in the population of Ehg on bean plants. Inactivation of the IAM pathway or cytokinin production did not affect epiphytic fitness. While the apparent transcriptional activity of iaaM-inaZ fusion increased slightly in cells of Ehg on bean and gypsophila leaves, compared with that in culture, very high levels of induction were observed in cells injected into gypsophila stems. In contrast, moderate levels of induction of ipdC-inaZ in Ehg were observed on leaves of these plants and in gypsophila stems, when compared with that in culture. These results suggest that the IAM pathway is involved primarily in gall formation and support the main contribution of the IpyA pathway to the epiphytic fitness of this bacterial species. PMID:9650296

Accumulation of intracellular ammonium and activities of the enzymes glutamine synthetase (GS) and glutamate dehydrogenase (GDH) were measured when the microalgae Chlorella vulgaris was immobilized in alginate with either of two wild type strains of Azospirillum brasilense or their corresponding indole-3-aceticacid (IAA)-attenuated mutants. After 48 h of immobilization, both wild types induced higher levels of intracellular ammonium in the microalgae than their respective mutants; the more IAA produced, the higher the intracellular ammonium accumulated. Accumulation of intracellular ammonium in the cells of C. vulgaris followed application of four levels of exogenous IAA reported for A. brasilense and its IAA-attenuated mutants, which had a similar pattern for the first 24 h. This effect was transient and disappeared after 48 h of incubation. Immobilization of C. vulgaris with any bacteria strain induced higher GS activity. The bacterial strains also had GS activity, comparable to the activity detected in C. vulgaris, but weaker than when immobilized with the bacteria. When net activity was calculated, the wild type always induced higher GS activity than IAA-attenuated mutants. GDH activity in most microalgae/bacteria interactions resembled GS activity. When complementing IAA-attenuated mutants with exogenous IAA, GS activity in co-immobilized cultures matched those of the wild type A. brasilense immobilized with the microalga. Similarity occurred when the net GS activity was measured, and was higher with greater quantities of exogenous IAA. It is proposed that IAA produced by A. brasilense is involved in ammonium uptake and later assimilation by C. vulgaris. PMID:25554489

Recently, we reported that UVB-activated indole-3-aceticacid (IAA) induces the apoptosis of G361 human melanoma cells. In the present study, we used IAA and visible light combinations to treat B16F10 melanoma-implanted nude mice using an experimental intense pulsed light (IPL) therapy model. We first investigated whether activated IAA by horseradish peroxidase (HRP) or UVB causes apoptosis of B16F10 melanoma cells. IAA/HRP or IAA/UVB combination lead to apoptosis of B16F10 cells, as reported in other cell lines. Interestingly, IAA alone was not cytotoxic. These findings suggested the potential use of IAA in the treatment of melanoma. For the future clinical use, we also tested whether visible light has the same effects like UVB and found that visible light also activates IAA to produce free radicals and that IAA/visible light decreased cell viability significantly. Based on these results, IAA/IPL combination was tried whether it can induce apoptosis in vivo status. TUNEL staining showed that IAA/IPL treatment induced apoptosis of tumor cells. In addition, the expressions of p53, Fas, and PARP were upregulated in the IAA/IPL-treated group than in untreated control, demonstrating that IAA/IPL treatment caused apoptosis in melanoma-implanted nude mice. In conclusion, we showed that IAA/IPL induces melanoma regression in B16F10 melanoma-implanted nude mice. These results suggest the potential use of IAA/IPL in the treatment of malignant melanoma. PMID:19301020

Acetate, a glial-specific substrate, is an attractive alternative to glucose for the study of neuronal-glial interactions. The present study investigates the kinetics of acetate uptake and utilization in the rat brain in vivo during infusion of [2-13C]acetate using NMR spectroscopy. When plasma acetate concentration was increased, the rate of brain acetate utilization (CMRace) increased progressively and reached close to saturation for plasma acetate concentration > 2-3 mM, whereas brain acetate concentration continued to increase. The Michaelis-Menten constant for brain acetate utilization ( KMutil=0.01±0.14mM) was much smaller than for acetate transport through the blood-brain barrier ( KMt=4.18±0.83mM). The maximum transport capacity of acetate through the blood-brain barrier ( Vmaxt=0.96±0.18?mol/g/min) was nearly two-fold higher than the maximum rate of brain acetate utilization ( Vmaxutil=0.50±0.08?mol/g/min). We conclude that, under our experimental conditions, brain acetate utilization is saturated when plasma acetate concentrations increase above 2-3 mM. At such high plasma acetate concentration, the rate-limiting step for glial acetate metabolism is not the blood-brain barrier, but occurs after entry of acetate into the brain. PMID:19393008

Acetate kinase, a member of the acetate and sugar kinase-Hsp70-actin (ASKHA) enzyme superfamily, is responsible for the reversible phosphorylation of acetate to acetyl phosphate utilizing ATP as a substrate. Acetate kinases are ubiquitous in the Bacteria, found in one genus of Archaea, and are also present in microbes of the Eukarya. The most well characterized acetate kinase is that from the methane-producing archaeon Methanosarcina thermophila. An acetate kinase which can only utilize PP(i) but not ATP in the acetyl phosphate-forming direction has been isolated from Entamoeba histolytica, the causative agent of amoebic dysentery, and has thus far only been found in this genus. In the direction of acetyl phosphate formation, acetate kinase activity is typically measured using the hydroxamate assay, first described by Lipmann, a coupled assay in which conversion of ATP to ADP is coupled to oxidation of NADH to NAD(+) by the enzymes pyruvate kinase and lactate dehydrogenase, or an assay measuring release of inorganic phosphate after reaction of the acetyl phosphate product with hydroxylamine. Activity in the opposite, acetate-forming direction is measured by coupling ATP formation from ADP to the reduction of NADP(+) to NADPH by the enzymes hexokinase and glucose 6-phosphate dehydrogenase. Here we describe a method for the detection of acetate kinase activity in the direction of acetate formation that does not require coupling enzymes, but is instead based on direct determination of acetyl phosphate consumption. After the enzymatic reaction, remaining acetyl phosphate is converted to a ferric hydroxamate complex that can be measured spectrophotometrically, as for the hydroxamate assay. Thus, unlike the standard coupled assay for this direction that is dependent on the production of ATP from ADP, this direct assay can be used for acetate kinases that produce ATP or PP(i). PMID:22214984

An international collaborative study of isotopic methods applied to control the authenticity of vinegar was organized in order to support the recognition of these procedures as official methods. The determination of the 2H/1H ratio of the methyl site of aceticacid by SNIF-NMR (site-specific natural isotopic fractionation-nuclear magnetic resonance) and the determination of the 13C/12C ratio, by IRMS (isotope ratio mass spectrometry) provide complementary information to characterize the botanical origin of aceticacid and to detect adulterations of vinegar using synthetic aceticacid. Both methods use the same initial steps to recover pure aceticacid from vinegar. In the case of wine vinegar, the determination of the 18O/16O ratio of water by IRMS allows to differentiate wine vinegar from vinegars made from dried grapes. The same set of vinegar samples was used to validate these three determinations. The precision parameters of the method for measuring delta13C (carbon isotopic deviation) were found to be similar to the values previously obtained for similar methods applied to wine ethanol or sugars extracted from fruit juices: the average repeatability (r) was 0.45 per thousand, and the average reproducibility (R) was 0.91 per thousand. As expected from previous in-house study of the uncertainties, the precision parameters of the method for measuring the 2H/1H ratio of the methyl site were found to be slightly higher than the values previously obtained for similar methods applied to wine ethanol or fermentation ethanol in fruit juices: the average repeatability was 1.34 ppm, and the average reproducibility was 1.62 ppm. This precision is still significantly smaller than the differences between various aceticacid sources (delta13C and delta18O) and allows a satisfactory discrimination of vinegar types. The precision parameters of the method for measuring delta18O were found to be similar to the values previously obtained for other methods applied to wine and fruit juices: the average repeatability was 0.15 per thousand, and the average reproducibility was 0.59 per thousand. The above values are proposed as repeatability and reproducibility limits in the current state of the art. On the basis of this satisfactory inter-laboratory precision and on the accuracy demonstrated by a spiking experiment, the authors recommend the adoption of the three isotopic determinations included in this study as official methods for controlling the authenticity of vinegar. PMID:19664468

Spoilage characterised by strong slime and gas formation affected some manufacture lots of an acetic-acid Baltic herring (Culpea haerengus membras) preserve after few weeks of storage at 0-6 degrees C. The product consisted of herring filets in aceticacid marinade containing sugar, salt, allspice and carrot slices. Microbiological analyses of the spoiled product showed high lactic acid bacterium (LAB) levels ranging from 4.5x10(8) to 2.4x10(9) CFU/g. Yeasts were not detected in any of the herring samples. Since LAB contaminants are seldom associated with fresh fish, LAB populations associated with marinade ingredients (carrots, allspice) were also analyzed. The highest LAB levels exceeding 10(7) CFU/g were detected in equilibrium modified atmosphere packaged baby carrots whereas the levels detected in the allspice samples did not exceed 4.3x10(5). A total of 176 randomly selected LAB isolates originating from herring, carrot and allspice samples were further identified to species level using a 16 and 23S rRNA gene RFLP (ribotyping) database. Leuconostoc gelidum and Leuconostoc gasicomitatum strains dominated both in the spoiled herring and carrot samples. These species are heterofermentative-producing CO(2) from glucose and they also produce dextran from sucrose. Inoculation of some commercial-herring products with spoilage-associated L. gelidum and L. gasicomitatum strains verified that these strains have the capability of producing slime and gas in herring preserves although slime formation was not as strong as in the original samples. Since L. gelidum and L. gasicomitatum strains were commonly detected in carrots, carrot slices used for the fish marinade were considered to be the probable source of these specific spoilage organisms. PMID:14698102

Diazotrophic bacteria were isolated, in two different years, from the rhizosphere and rhizoplane of coffee (Coffea arabica L.) plants cultivated in Mexico; they were designated as type DOR and type SAd isolates. They showed characteristics of the family Acetobacteraceae, having some features in common with Gluconacetobacter (formerly Acetobacter) diazotrophicus, the only known N2-fixing species of the aceticacid bacteria, but they differed from this species with regard to several characteristics. Type DOR isolates can be differentiated phenotypically from type SAd isolates. Type DOR isolates and type SAd isolates can both be differentiated from Gluconacetobacter diazotrophicus by their growth features on culture media, their use of amino acids as nitrogen sources and their carbon-source usage. These results, together with the electrophoretic mobility patterns of metabolic enzymes and amplified rDNA restriction analysis, suggested that the type DOR and type SAd isolates represent two novel N2-fixing species. Comparative analysis of the 16S rRNA sequences revealed that strains CFN-Cf55T (type DOR isolate) and CFN-Ca54T (type SAd isolate) were closer to Gluconacetobacter diazotrophicus (both strains had sequence similarities of 98.3%) than to Gluconacetobacter liquefaciens, Gluconacetobacter sacchari (similarities < 98%) or any other acetobacteria. Strain CFN-Cf55T exhibited low levels of DNA-DNA reassociation with type SAd isolates (mean 42%) and strain CFN-Ca54T exhibited mean DNA-DNA reassociation of 39.5% with type DOR isolates. Strains CFN-Cf55T and CFN-Ca54T exhibited very low DNA reassociation levels, 7-21%, with other closely related acetobacterial species. On the basis of these results, two novel N2-fixing species are proposed for the family Acetobacteraceae, Gluconacetobacter johannae sp. nov. (for the type DOR isolates), with strain CFN-Cf55T (= ATCC 700987T = DSM 13595T) as the type strain, and Gluconacetobacter azotocaptans sp. nov. (for the type SAd isolates), with strain CFN-Ca54T (= ATCC 70098ST = DSM 13594T) as the type strain. PMID:11491326

The project experimentally investigated using biomass as feedstock for conversion to calcium magnesium acetate (CMA), an alternative road salt. This new organic road salt will prevent corrosion of bridge decks, underground cables, and rusting of cars and trucks. CMA from biomass will reduce costs, compared to petroleum and natural gas for making this material. Phase I work focused on bioconversion of sewage sludge residuals to CMA. The process is based on a packed bed fermenter to produce aceticacid from biomass, as well as liquid ion exchange to recover aceticacid from the fermenter broth prior to the final production step which occurs by passing the aceticacid over limestone. In Phase I: (1) percent bioconversion and kinetics of biomass to aceticacid have been confirmed in small batch fermenters; (2) equilibrium constants for aceticacid recovery via liquid ion exchange have been documented; and (3) rates of conversion to CMA have been determined.

The title compound, C31H48O7·0.04CH3COOH, is a polyoxy­genated steroid obtained by selective chemical oxidation of 7-de­hydro­cholesteryl acetate. The asymmetric unit comprises three mol­ecules of the steroid (Z? = 3) and a mol­ecule of aceticacid which has occupancy factor 0.131?(5). The geometric parameters of the independent mol­ecules do not reveal significant differences. In one mol­ecule, the terminal isopropyl group is disordered over two sets of sites with occupancy ratio 0.869?(5):0.131?(5). The three mol­ecules reveal different hydrogen-bonding patterns. Each of them is involved in an intra­molecular S(6) hydrogen-bonding motif, involving hy­droxy groups as donor and acceptor. In the crystal, two independent mol­ecules form dimers through hydrogen bonding between an OH donor and an acetate carbonyl acceptor, giving rise to R 2 2(16) ring patterns. A single hydrogen bond between the OH group and a ketone carbonyl group is observed between two symmetry-independent mol­ecules. PMID:23795056

Growth energetics of the aceticacid bacterium Acetobacter pasteurianus were studied with aerobic, ethanol-limited chemostat cultures. In these cultures, production of acetate was negligible. Carbon limitation and energy limitation were also evident from the observation that biomass concentrations in the cultures were proportional to the concentration of ethanol in the reservoir media. Nevertheless, low concentrations of a few organic metabolites (glycolate, citrate, and mannitol) were detected in culture supernatants. From a series of chemostat cultures grown at different dilution rates, the maintenance energy requirements for ethanol and oxygen were estimated at 4.1 mmol of ethanol (middot) g of biomass(sup-1) (middot) h(sup-1) and 11.7 mmol of O(inf2) (middot) g of biomass(sup-1) (middot) h(sup-1), respectively. When biomass yields were corrected for these maintenance requirements, the Y(infmax) values on ethanol and oxygen were 13.1 g of biomass (middot) mol of ethanol(sup-1) and 5.6 g of biomass (middot) mol of O(inf2)(sup-1), respectively. These biomass yields are very low in comparison with those of other microorganisms grown under comparable conditions. To investigate whether the low growth efficiency of A. pasteurianus might be due to a low gain of metabolic energy from respiratory dissimilation, (symbl)H(sup+)/O stoichiometries were estimated during acetate oxidation by cell suspensions. These experiments indicated an (symbl)H(sup+)/O stoichiometry for acetate oxidation of 1.9 (plusmn) 0.1 mol of H(sup+)/mol of O. Theoretical calculations of growth energetics showed that this low (symbl)H(sup+)/O ratio adequately explained the low biomass yield of A. pasteurianus in ethanol-limited cultures. PMID:16535681

The performance of silver-loaded zeolite (HY and HZSM-5) catalysts in the oxidation of butyl acetate as a model volatile organic compound (VOC) was studied. The objective was to find a catalyst with superior activity, selectivity towards deep oxidation product and stability. The catalyst activity was measured under excess oxygen condition in a packed bed reactor operated at gas hourly space velocity (GHSV)=15,000-32,000 h(-1), reaction temperature between 150 and 500 degrees C and butyl acetate inlet concentration of 1000-4000 ppm. Both AgY and AgZSM-5 catalysts exhibited high activity in the oxidation of butyl acetate. Despite lower silver content, AgY showed better activity, attributed to better metal dispersion, surface characteristics and acidity, and its pore system. Total conversion of butyl acetate was achieved at above 400 degrees C. The oxidation of butyl acetate followed a simple power law model. The reaction orders, n and m were evaluated under differential mode by varying the VOC partial pressure between 0.004 and 0.018 atm and partial pressure of oxygen between 0.05 and 0.20 atm. The reaction rate was independent of oxygen concentration and single order with respect to VOC concentration. The activation energies were 19.78 kJ/mol for AgY and 32.26 kJ/mol for AgZSM-5, respectively. PMID:18294771

Treatment of saccharidic polyols in ethyl acetate with catalytic sulfuric acid leads to the corresponding primary monoacetate derivatives in good yields. The transesterification was realized by simple stirring without rigorous exclusion of moisture or oxygen. Our protocol is applicable to the regioselective monoacetylation of amino sugars having different substituents at the 2-positions.

... (1) The chemical substance identified as aceticacid, 2-methoxy-, methyl ester (PMN P-99-0365, CAS No. 6290-49-9) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of...

The extent of syntrophic acetate oxidation (SAO) and the levels of known SAO bacteria and acetate- and hydrogen-consuming methanogens were determined in sludge from 13 commercial biogas production plants. Results from these measurements were statistically related to the prevailing operating conditions, through partial least squares (PLS) analysis. This revealed that high abundance of microorganisms involved in SAO was positively correlated with relatively low abundance of aceticlastic methanogens and high concentrations of free ammonia (>160 mg/L) and volatile fatty acids (VFA). Temperature was identified as another influencing factor for the population structure of the syntrophic acetate oxidising bacteria (SAOB). Overall, there was a high abundance of SAOB in the different digesters despite differences in their operating parameters, indicating that SAOB are an enduring and important component of biogas-producing consortia. PMID:24333792

1. The tricarboxylic acid and glyoxylate cycles are of major importance in the assimilation of acetate and propionate by Prototheca zopfii. The pattern of assimilation of [2-14C]acetate and [2-14C]propionate by whole cells growing with their respective substrates is similar except that, with propionate, ?-hydroxypropionate is the first labelled intermediate detected. 2. Carbon dioxide fixation is of little quantitative importance for the growth of this organism with propionate. 3. The yield of cells obtained/mole of acetate is similar to that obtained/mole of propionate and about half that obtained/mole of n-butyrate, these substrates acting as sole sources of carbon and energy. PMID:16749100

To date, the literature on the treatment of individuals who have committed sexual offenses has focused primarily on psychotherapeutic interventions and the use of antiandrogens. Recently case reports and small series supporting the efficacy of other psychiatric medication, such as serotonin reuptake inhibitors, have been published. Only a few publications have looked at the efficacy of leuprolide acetate, an LH-RH

Reliable method now available for joining parts of this difficult-tobond material. Heating fixture encircles ethylene vinyl acetate multiplesocket part, providing heat to it and to tubes inserted in it. Fixtures specially designed to match parts to be bonded. Tube-and-socket bonds made with this technique subjected to tensile tests. Bond strengths of 50 percent that of base material obtained consistently.

We examined gazelle peripheral blood leucocytes using the alpha-Naphthyl acetate esterase (ANAE) staining technique (pH 5.8). Our purpose was to determine the percentage of ANAE positive lymphocytes. The proportion of ANAE positive T-lymphocytes was 72%. T-lymphocytes showed an ANAE positive reaction, but eosinophilic granulocytes and monocytes also showed a positive reaction. By contrast, no reaction was detected in B-lymphocytes, neutrophil granulocytes or platelets. The reaction observed in T-lymphocytes was a red-brown coloration, usually 1-2 granules, but enough granules to fill the cytoplasm were detected rarely. As a result of ANAE enzyme staining, we concluded that the staining technique can be used as a cytochemical marker for gazelle T-lymphocytes. PMID:19085516

The quantitative contribution of fatty acids and COâ to methanogenesis was studied by using stirred, 3-liter bench-top digestors fed on a semicontinuous basis with cattle waste. The fermentations were carried out at 40 and 60Â°C under identical loading conditions. In the thermophilic digestor, acetate turnover increased from a prefeeding level of 16 ..mu..M\\/min to a peak (49 ..mu..M\\/min. Acetate turnover

Ethyl acetate extracts of olive mill waste water (OMWW) were prepared, under in optimal conditions, using a continuous counter-current extraction unit. The antiradical and antioxidant activities of the OMWW extract as well as pure phenolic compounds identified in this extract were evaluated. Results showed that pure hydroxytyrosol and 3,4-dihydroxyphenyl aceticacid had the highest radical-scavenging effects on 1,1-diphenyl-2-picrylhydrazyl radical and

A sequential three-component synthesis of functionalized benzisothiazoline-3-aceticacid 1,1-dioxides utilizing a domino Heck-aza-Michael pathway is reported. This one-pot procedure rapidly assembles functionalized benzylsulfonamides, which undergo a palladium-catalyzed, domino, Heck-aza-Michael transformation in an experimentally straightforward manner. This attractive protocol has been utilized to synthesize three combinatorial sublibraries (I-III) comprising a total of 95 compounds in high purities (> or =95% for 75 compounds), yield and quantities. PMID:19505109

A sequential three-component synthesis of functionalized benzisothiazoline-3-aceticacid 1,1-dioxides utilizing a domino Heck-aza-Michael pathway is reported. This one-pot procedure rapidly assembles functionalized benzylsulfonamides, which undergo a palladium-catalyzed, domino, Heck-aza-Michael transformation in an experimentally straightforward manner. This attractive protocol has been utilized to synthesize three combinatorial sub-libraries (I-III) comprising a total of 95 compounds in high purities (?95% for 75 compounds), yield and quantities. PMID:19505109

An operationally friendly, two-step, one-pot process has been developed for the rapid synthesis of carbon-11 labeled indole-3-aceticacid ([11]IAA or [11]auxin). By replacing an aprotic polar solvent with tetraethylene glycol, nucleophilic [11]cyanation and alkaline hydrolysis reactions were performed consecutively in a single pot without a time-consuming intermediate purification step. The entire production time for this updated procedure is 55 min, which dramatically simplifies the entire synthesis and reduces the starting radioactivity required for a whole plant imaging study.

The aim of this paper is to study the corrosion resistance of hybrid films. Tin plate was coated with a siloxane-poly (methyl methacrylate) (PMMA) hybrid film prepared by sol-gel route with covalent bonds between the organic (PMMA) and inorganic (siloxane) phases obtained by hydrolysis and polycondensation of 3-(trimethoxysilylpropyl) methacrylate (TMSM) and polymerization of methyl methacrylate (MMA) using benzoyl peroxide (BPO) as a thermic initiator. Hydrolysis reactions were catalyzed by aceticacid solution avoiding the use of chlorine or stronger acids in the film preparation. The effect of the addition of tetraethoxysilane (TEOS) on the protective properties of the film was evaluated. The hydrophobicity of the film was determined by contact angle measurements, and the morphology was evaluated by scanning electron microscopy (SEM) and profilometry. The local nanostructure was investigated by Fourier transform infrared spectroscopy (FT-IR). The electrochemical behavior of the films was assessed by open circuit potential monitoring, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements in a 0.05 M NaCl solution. The mechanical behavior was evaluated by tribology. The results highlighted that the siloxane-PMMA hybrid films modified with aceticacid are promising anti-corrosive coatings that acts as an efficient diffusion barrier, protecting tin plates against corrosion. However, the coating properties were affected by the TEOS addition, which contributed for the thickness increase and irregular surface coverage.

The simultaneous capillary GC determination of underivatized antiandrogen cyproterone acetate (CPA) and its active metabolite 15?-hydroxycyproterone acetate (OH-CPA) in spiked urine was performed on a flexible VCOT quartz capillary column, coated with a non-polar CP-Sil 5 CB liquid phase. A split\\/splitless injector and a flame-ionization detector were used. Equilin was used as an internal standard, and resolution of all the

Indole-3-aceticacid (IAA) was measured in leaves and roots of tomato (Lycopersicon esculentum) genotypes subjected to salt stress. An abscisic acid (ABA)-deficient mutant of tomato (sitiens), the genetic parent (Rheinlands Ruhm, RR), and a commercial variety (Large Cherry Red, LCR) of tomato were treated with 50 to 300 mM NaCl in nutrient culture. Both LCR and RR had significantly higher levels of IAA in the roots compared with that in sitiens prior to treatment. The initial levels of IAA in the roots of LCR and RR declined by nearly 75% after exposure to NaCl, whereas those in roots from the sitiens mutant remained unchanged. IAA levels in the leaves of all genotypes remained unchanged or increased slightly in response to NaCl. ABA was highest in leaves from the normal genotypes after exposure to NaCl. ABA levels in the roots of sitiens were similar to the levels in the normal genotypes, whereas levels in the leaves were only 10% of the levels found in normal genotypes regardless of the salt treatment. Treatment of LCR and sitiens with exogenous ABA increased the ABA levels in leaves and roots, but there were no measurable changes in endogenous IAA. Therefore, the reduction in IAA appears to result from an ABA-independent effect of NaCl on IAA metabolism in the roots of stressed plants. PMID:12226396

An acetate-fermenting strain of Methanosarcina was isolated from an acetate enrichment culture inoculated with anaerobic sludge from a waste treatment digestor. In pure culture, this organism fermented acetate in the absence of added hydrogen at rates comparable in magnitude to those found in digestor systems. This rate was significantly higher than previously obtained for pure cultures of this genus. Mineral components of yeast extract were highly stimulatory for cultures growing on methanol. Comparable stimulation was not observed for cultures growing on acetate. Labeling studies indicated that acetate was converted to methane and CO2 as predicted by previous studies on mixed cultures. Total oxidation or reduction of acetate was not the mechanism of conversion of acetate to methane by the pure culture. The ability of this strain to form colonies or to produce methane from acetate was apparently influenced by the choice of substrate and conditions used for growing the inoculum. PMID:677880

The addition of acetate to uranium-contaminated aquifers in order to stimulate the growth and activity of Geobacter species that reduce uranium is a promising in situ bioremediation option. Optimizing this bioremediation strategy requires that suf?cient acetate be added to promote Geobacter species growth. We hypothesized that under acetate-limiting conditions, subsurface Geobacter species would increase the expression of either putative acetate symporters genes (aplI and aplII). Acetate was added to a uranium-contaminated aquifer (Ri?e, CO) in two continuous amendments separated by 5 days of groundwater ?ush to create changing acetate concentrations. While the expression of aplI in monitoring well D04 (high acetate) weakly correlated with the acetate concentration over time, the transcript levels for this gene were relatively constant in well D08 (low acetate). At the lowest acetate concentrations during the groundwater ?ush, the transcript levels of aplII were the highest. The expression of aplII decreased 2–10-fold upon acetate reintroduction. However, the overall instability of acetate concentrations throughout the experiment could not support a robust conclusion regarding the role of apl genes in response to acetate limitation under ?eld conditions, in contrast to previous chemostat studies, suggesting that the function of a microbial community cannot be inferred based on lab experiments alone.